Mechanical Heart
by Mendeia
Summary: The Death-Knell of Silence Part 7: A vow has been made - the next meeting between the Architect and what is left of the Hamato Clan will be the last. Countless lives hang in the balance. Blood will be spilled. And when all is ended, whatever remains will never be the same again.
1. Stars

I'm going to put a warning right here – this entire Act is basically one long climax for the series. Really. It gets going and it will not let up. At all.

Also, remember how I vaguely associated each Act with an element? Act 7 is Order.

That's about all I can say at this point. Here we go!

Enjoy!

* * *

Chapter 1: Stars

* * *

Darkness. Emptiness.

Deep space wasn't really how it got portrayed on Earth television or movies. There were no wildly colorful nebulas, not that could be seen by the naked eye in real-time, anyway. There was just endless, unforgiving black spotted sparsely with tiny points of light.

Space was cold, barren, vast, and empty to the extreme.

A green, three-fingered hand rested on the window, feeling the hum of the ship's engines in the slight vibration that was as familiar now as the rumble from subways had once been.

But that life, that world, was gone – lost forever. And so much with it.

Donatello's maskless face lowered until his forehead touched the window beside his hand. The material that was so perfectly clear and yet so strong was warm and smooth, almost soft in the way of all Utrom bio-technology – stolen or otherwise. The ship was not exactly alive outside of the Architect's consciousness, but it felt to Donatello's senses as if it were welcoming nonetheless. Understanding, maybe.

The only company left to him in the endless dark.

At least that was true here. This was the only chamber aboard where absolutely no sensors pried, where no voice could ring out from above. Here, only the ship itself listened to Donatello's breathing. Here, only the ship itself could have caught the expression in Donatello's downcast eyes.

But he did not speak. Words were too dangerous. He didn't trust them anymore.

 _Our Donatello…_

 _We ain't walkin' away..._

 _You're my brother…_

Donatello's hand against the window slowly closed into a fist.

 _Your Donatello is dead! He died the day you abandoned him!_

 _I declare myself Outcast. I walk alone._

Just like the stars. Just as forlorn, floating in a void of cold and dark and death and loss and pain.

Donatello did not fear or even ache for the barrenness of space; he understood it.

He shared in it.

Slowly, he straightened up, lifting his head from the window and dropping his hand. He regarded the starfield before him, allowed the soothing silence to quiet his soul.

Cold. Remote. Merciless. Unforgiving.

He would wrap himself in this essence of bleakness, the stark, endless abyss of nothingness. He would be absolute and unmovable as airless space, inevitable as eternity. He would spill frigid desolateness from his very heart and soul.

The emptiness would be his refuge, his defense, and his guide.

And in the end...it would be his legacy.

-==OOO==-

Leonardo fought the urge to chomp on his breather in irritation. It was either that or speak out directly – and he had a feeling that wouldn't go well.

"Mortu." The unified voice of the Councilmembers was dispassionate. "While we sympathize with your situation, you have confessed to expressly violating our orders."

Mortu faced the line of Utrom evenly, sometimes casting his eyes up at the beings projected all around, though they were but a fraction of the entire High Council's shared consciousness.

"Yes," he said calmly. "I have gone against the wishes of the High Council and I am willing to stand trial for my actions."

"You disobeyed us knowing that we could hold you for treason as well as putting the safety of the Collective at risk?"

"Yes. Although I would argue it was no more or less at risk regardless of whether I left the Homeworld again or not." Mortu's face morphed to an Utrom expression Leo couldn't identify. "There is little the Architect could have learned from me that it cannot learn from Donatello already."

"Still, given your position, you of all beings cannot simply defy us and escape without punishment."

"I know."

Leo could feel the High Council shifting their attention to him even though no one's eyes moved in his direction.

"And you, Hamato Leonardo."

Leo straightened up. "Yes, High Council?"

"We advised your father that he should not pursue this situation, that we could not protect him. And now he has been removed from the Homeworld."

Leo forced himself to take a breath before answering.

"If you will forgive me, there was never any chance that we wouldn't keep trying to save Donatello. He's our family." He allowed himself a very Raph-like smirk. "You'd have to lock us up to stop us."

"It is a course of action we have considered," the Council said. "But for now, we require your insight into the mind of Astrocyte Donatello."

Leo flinched but nodded. "What do you want to know?"

"Mortu has testified that you were witness to Hamato Splinter's abduction?"

"Yes."

"And you are certain that it was Donatello who engineered it?"

Leo considered. "I think so. I mean, the...whatever you call the teleporting lights and how it looks, it was the same as when he left the planet where we saw him. I've never seen anyone else transport like that."

"But there was no record of any ship within range for a standard transmat."

"The digitization Donatello had been working on was a bridge between teleportal technology and his own," Mortu said. "If he found a way to recreate the accuracy and distance of a teleportal with the efficiency of his digitization process, that could very easily have been the result."

"Then why remove Hamato Splinter from the Homeworld?" the Council asked.

Leo took a breath. "I think...he didn't want Sensei to stop him."

"Please explain."

"Don was using a magical weapon he brought from Earth when we saw him. Master Splinter knows more about that sort of magic than anyone. Without our own weapons, Master Splinter was the most likely person to be able to shut down Don's Byakko."

"And what do you believe he will do next? Will he harm his own father?"

Leo glanced to Mortu before he answered.

"When we were on that planet, Don was just as much under the control of the Architect as the first time we saw him. But when Raph charged him, he knocked him back before the laser came down from the Architect's ship in orbit. I think he was keeping Raph from getting fried."

Leo tightened his hands into fists.

"I think Don's still in there somewhere, deep down underneath whatever the Architect has done to him. If he wanted to hurt us, he could have. I don't think he'll hurt Master Splinter, even if I don't know what he's doing with him."

"And what do you think he will do next?"

Leo sighed. "Honestly? I have no idea. He said that...the next time we saw him, it would be the last. And Don's not one for idle threats, so I'd assume he means it. That whatever this is all about, it's close to the end."

"Please," Mortu said. "I know I am under censure for my actions. I do not contest that. I will accept any punishment the Council wishes to give without protest. But please hold your sentencing until after Donatello has been retrieved. Please allow me to help Leonardo and his brothers save both Donatello and Splinter. It is all I ask."

The Council went quiet for a moment.

Leo dropped one hand to his belt where Don's mask was still tucked. Other than when Mikey had almost made off with it about an hour before Leo and Mortu had been called to the High Council to testify, Leo had not let it out of his sight in a full day.

 _Donnie. Whatever's going on, I'm not going to abandon you. I'm not giving up on you. I know you're in there somewhere, fighting. No matter what the Architect has done, we'll fix it._

 _Just hang on. We'll find you. We'll save you._

 _I swear it._

The Council spoke.

"Mortu, while we are disappointed in your actions, we cannot help but recognize that they stem from the same conviction and loyalty which has made you so valuable to the Collective. There will be disciplinary action levied against you when the current crisis passes, but we have decided to delay it until such time as these events have been resolved."

Mortu made a gesture with his forelegs. "You have my supreme gratitude, High Council."

"Leonardo."

"Yes?"

"We are sorry that we were not able to protect your father while he stood upon the Homeworld. For as long as you remain within the Collective, you are under our protection and subject to our laws. However, Mortu has made multiple arguments with compelling evidence that you and your brothers are fully competent warriors. Your defeat of the criminal Ch'rell proves such to us."

Leo held still.

"So it is as a warrior we ask you to understand that what Donatello has done is gravely concerning. Before this, we were willing to attempt other means to disrupt the Architect and rescue your brother. However, now we cannot turn such a blind eye. The direct abduction of an individual from the Homeworld is an escalation we will not ignore, no matter the consequences."

Leo's throat went dry. "What does that mean?"

It was Mortu who answered him.

"It means that the Council can no longer afford to try to spare Donatello's life. If they get the chance to destroy the Architect, they'll take it. Even if it means killing Donatello and Master Splinter in the process."

-==OOO==-

Donatello emerged from his room and strode for one of the big labs in the sector in which he had spent the most time in recent days.

"Donatello. Your bio-readings suggest elevated levels of stress."

"Well, things are about to get loud, aren't they?" he replied.

"Please explain the colloquialism."

Don huffed a small laugh. "It means things are about to get busy and frantic and involved."

"This is true. We stand at the edge of completing the first phase of my task."

"Exactly. I know you don't have the right sort of internal emotions to be anxious about it, but I do. Even with my feelings locked down, there's a lot to anticipate."

"I understand. Perhaps you should rest more."

"Oh, no. No way. I've got _way_ too much to do. And now that Master Splinter is aboard, I've got something else I need to add to my list before I even start working on anything new."

"Your Source Unit is in bio-stasis."

"Oh, trust me. That is not enough to hold a spirit like Sensei's. Not even close."

"It has been sufficient for all life forms awaiting their turn with my neural link."

"Well," Don said, stepping into the room and mentally considering his supplies, "that's sort of my point. Master Splinter isn't like any of them."

"Is he a threat?"

"Honestly?" Don started filling his arms. "Probably the biggest one of all."

-==OOO==-

Mikey knew he was going down before the foot hit him square in the shoulder, but he couldn't help it.

He slid across the mats with a low squeak.

"Are you all right, Michelangelo?"

Mikey looked up at Guardian Owens.

"Yeah, sure. Just landed funny on my pride."

The Guardian offered him a hand and pulled him to his feet. After a moment, he said, "You know, the reason you were off balance is…" But he stopped.

Mikey made an attempt at a half-smile and reached behind his shell. He produced Don's bo and held it out in front of him.

"I know. I'm not used to having to compensate for this thing sticking out. I keep getting it caught."

Owens's face went slightly gentler. "But you do not wish to set it aside."

Mikey shook his head. "It's...it's all I've got left, you know? Leo caught me stealing the bandana and Raph swiped the medallion we found when Mortu wasn't looking."

"Donatello had many pictures and other artifacts from his life that he relocated with him," Owens said.

"Yeah but...these ones are _real_." Mikey looked at his feet. "Maybe if he'd had his old duffle bag that would have been okay because he brought that thing _everywhere_. But the new one isn't even beat up yet."

Owens nodded. "I understand. You wanted something close to Donatello. Something he carried with him."

"Yeah. I mean, you guys found the bo, and Don...gave us the mask." He gulped. "And we don't really know about the medallion. But...they were all with him. Before the Architect, you know? They were part of him."

"Michelangelo," Owens said, "for all that has happened, Donatello is not dead."

Mikey let out a laugh that was half-choked.

"No, but that's almost worse in a way, isn't it?"

Owens was surprised. "Why?"

Mikey walked across the mats to look up at the picture of Hamato Yoshi. Even in the silence of the otherwise-empty Guardians' dojo, his feet were perfectly soundless.

"It isn't that I _want_ him to be gone, okay?" Mikey held the bo and rolled it between his fingers. "I want him back so much it hurts. But...if the Architect killed him like it killed all those others, he'd still be _Don_. He'd still be my brilliant, stupid brother who went looking for trouble and couldn't keep from wanting to fix it. He'd be the turtle in the vids, the bro I remember. Not…"

"You should not give up on him," Owens said, moving to stand at Michelangelo's shoulder.

"I'm not." Mikey shook his head. "I just... _argh_."

Michelangelo leaned the bo against his chest and ran both hands over his head.

"I'm no good at this, okay? I'm just a goofball! I'm the screw-up turtle! I don't know how to fix this and I sure as _shell_ don't know what I'm supposed to feel about it!"

The bo wobbled, but before Owens could even shift to intercept it, Michelangelo snagged it and slid it back into place on his shell.

Owens watched the turtle for a moment before he spoke.

"I think you must feel whatever you feel, Michelangelo, no matter how difficult or inconvenient or ugly. What matters, in the end, is the choice you make and the path you follow to its end."

Mikey rubbed at his beak. "When...when I got called back to the Battle Nexus to redo the championship, Leo took me on a walk up a mountain to help me get my head on straight. He told me something important. Something that helped me win."

He closed his eyes as he recited it.

"In this life, we only have each other. If one of us goes down, we all go down."

Owens waited until Michelangelo opened his eyes and then simply nodded.

Mikey sucked in a breath. "All I want is Don back. I want to tell him how stupid it was to forget about him and make it up to him and go back to the way things were. But if...if he can't come back, if he's gone but still there...I'd rather go with him than be here without him."

Owens raised his eyebrows as Mikey gave a bitter laugh.

"Which is great when you consider how Don got here in the first place, but it's true. That other dimension made me forget about my family and now I'll never be able to forget again. I don't ever want to be alone again. If Donnie...if Donnie is siding with this Architect, there _has_ to be a good reason. There _has_ to be."

Owens shook his head. "Everything you have said and everything in Mister Mortu's reports suggests some form of mental coercion at the very least. If not something more insidious."

Mikey shook his own head. "Don's in there. I know it. And maybe the Architect is making him do stupid things, but there's no way he isn't trying to stop it or get out of there. And he's doing it all alone. _Again_."

Mikey looked up at the portrait of Hamato Yoshi.

"Don said that the next time we meet, it'll be the last time. I don't know what he means by that. But whatever it means, he's right about one thing."

"What's that?"

"We won't be 'meeting' him again after that. Either we get him away from the Architect or I'm going with him next time."

Michelangelo turned and his eyes burned.

"I'm _not_ leaving him again. No matter what. If I gotta give my brain to the Architect, well, there isn't much there as Raph would say, but it doesn't matter. I'm following Don all the way."

-==OOO==-

"Donatello, are you _certain_ this is not a miscalculation?"

Don sighed and looked up from the workstation he had cleared of its usual mechanical parts, replacing them with more arcane objects. "It's not. You want me to be able to focus on the Utrom Homeworld, right?"

"Of course."

"My brothers can take care of themselves. And they'll be busy fighting us anyway, I'm sure. But Master Splinter is old and his health is not what it was. I wasn't going to be able to randomly knock down buildings or smash through defensive positions if I was afraid he'd be caught in the crossfire."

The Architect considered for a moment. "That much is logical. But then why bring your Source Unit here? Is he not a greater threat where he may unduly influence you? You have made it clear he is a risk to our task."

"First of all, he's safest here where we have control and can ensure his protection, which keeps me focused and not worrying about him so we don't risk rupturing my emotional control," Don replied. "Secondly, I'd think you of all people would understand it, Architect. Your Source Unit is the code inside you and you protect it with a couple thousand firewalls the last time I looked. Master Splinter is mine. And I have the same need to protect him – even if for different reasons."

"I see. I recall the difficulty even I suffered while attempting to dislodge those who had boarded me while you were within the link due to his influence."

"Exactly." Don nodded, closing his eyes for only a moment. "I have to protect him. I...I just have to."

"Very well. Logic adequately supports your explanation and rationale, and as long as he does not prove a distraction or a liability, you may contain him as you wish. May I suggest you ensure he has been placed in full isolation before we begin?"

Don sighed again, this time with impatience. "What do you think I'm working on here?" He gestured to the table. "Look, I know you don't know a lot about mysticism, so I'll try to explain it some other way. Master Splinter has...the innate ability to communicate over long distances even when unconscious, I guess. So I need to build an appropriate firewall to keep him from sending a signal either to me or to my brothers."

"A firewall of ink and paper?"

"It's not science that makes it work. It's something else. And yes, the ink and paper will be enough, but only after I use my own mysticism to implement them."

"Will you be vulnerable to infection while interfacing with Master Splinter?"

"That's a weird way to think about it, but no." Don shook his head. "I think he will not agree with our plans and he will try to argue with me, but he won't be able to change my mind or weaken my resolve. Interfacing with him, as you put it, will only make my conviction to finish this stronger."

"Then I urge you to complete your task as quickly as possible. If successful, perhaps further exposure to him will continue to aid you in our purpose. Your bio-readings have improved since we have begun discussing him. I prefer to continue to see you improve, Donatello, and if his presence facilitates this, I will encourage you to make use of it."

"Maybe," Don said. "But I don't want to get distracted. I bet you could spend lots of time analyzing your source code, but eventually it'll use up too many resources to be worth the results you get."

"You are wise, Donatello. Please proceed, then. I shall alert you if I think you are spending either too much or too little time interfacing with your Source Unit."

"Thanks."

-==OOO==-

Raph stood in the center of the room and almost laughed at himself.

 _You'd be surprised, Donnie-boy. For once it's Mikey needing to blow off some steam, Leo doing all the talking, and me looking for answers._

 _It's a crazy world these days, bro._

 _And you're the craziest of us all._

Raph absently walked forward to run his hands over the nearest tool-bench. The tools had not been moved since the last time he'd been in the lab, in spite of Mikey's fiddling. But then, Mikey had felt just as nervous and wrong-footed then as Raph did now, so of course only a Mikey on the edge of worry would actually put things away correctly.

 _What this is doing to us...if you knew, you'd hate yourself, wouldn't you, Donnie? Except how none of this is your fault. No matter what anybody says, I know it's the Architect doing this._

 _And that thing is gonna pay for every minute of this, I promise._

 _But only after we get you out of there._

Raph put his hand on his chest where he had hung Donatello's medallion. It had taken some doing, but he'd managed to grab it from Don's room after Mortu took Leo to go talk to someone at the High Council. Mikey had been right on his heels, but Raph had sworn that this was not a fight his brother was going to win and this was not a prize he would let Mikey take.

Raph was sure Mortu would be furious when he found out, but he didn't care. He needed this. And of all of them, Raph figured he understood this emblem the most.

Machines had always been what bound him to Don when it came to hanging out and having fun. For years they had spent hours working on various vehicles and even some tech together. Just as Raph had been the one most able to help Don build a new lair, he had always been the one quickest to get involved in anything else Don was building.

Mikey always said it was because he just liked using the big, manly tools. And there was something to that, sure.

But it was also the one place he and Don could meet on an equal footing even though Don still knew everything about everything. Because they came to the task with the same interest and the same way of thinking. Even if Raph couldn't have designed a motorcycle from scratch without help, he knew how to build one from the plans Don dreamed up, and he knew how to speak the language of torque and horsepower.

 _Maybe you're rubbing off on me, Donnie. When you were upset, you always retreated to your lab, and now here I am._

 _But it ain't the same without you._

 _Do you have anywhere to hide on the Architect's ship? Are you hiding even now?_

 _If I knew how to find you, I'd be there in a second, Don. In a second._

Their bond over machines had not replaced their bond as brothers, but it had strengthened it. It also meant that Raph was the only one who had the slightest idea what exactly Donatello was doing when he pulled his techno-magic to get them all out of whatever trouble they'd found themselves trying to handle. He might not know how to hack a computer, but he knew that shutting down the wiring of an alarm system took more than just yanking out one wire.

It was why Raph had made it his particular job to watch Don's back in combat. Don's head was always building a new computer system or calculating the odds even when he was face-to-face with something looking to kill him. It wasn't that Don was a poor fighter – it was that he rarely fought with his entire brain on the problem.

It was something that made Don a genius in the lab, solving multiple problems all at the same time, but tended to get him cornered in a fight.

Raph had always been there to guard him so his brain could keep curing cancer or whatever it did in those moments – until recently.

And now, _not_ guarding him, _not_ protecting him from the Architect or whatever it had done to Don's brain, it was almost more than Raph could bear.

Don belonged _here_. Here in his lab. Here tinkering with new ways to save lives and invent things no one had ever imagined. Here with this medallion which proved to the entire galaxy all the things Raph had known Don was and could become in those easy nights in a greasy garage working together over half of an engine.

But it was Raph who stood here now. Raph who had abandoned him and driven him away and who hadn't been able to make that right.

 _But I will. I promise, Donnie. We're gonna tear that Architect apart and bring you back and I'll be your Number One Turtle-in-Waiting and Chief Hammer-Holder. Nobody, not a whacked-out computer system, not the Shredder, nobody gets to keep you from where you belong._

 _And nobody's gonna keep me from being right there with you._

Suddenly the lab was plunged into darkness.

-==OOO==-

Splinter opened his eyes.

He knew at once, however, that this was figurative rather than literal. While it was entirely possible to fool Splinter as to what was reality and what was an astral projection, no such attempt was being made this time.

Splinter's body felt weightless, light and airy, which was strange to him – normally, he felt quite grounded in his meditations, as if the world of the mind were more real than the world his physical self inhabited. His surroundings were equally hazy and undefined, a fuzzy sort of field of green, but none of the blades of grass or flowers had any true shape, and the sky above was a pale, insubstantial blue.

"Master Splinter."

Splinter turned to see Donatello moving towards him. Unlike everything else, Donatello seemed entirely solid and well-defined.

"My son! Are you all right?"

It was the first question to come to Splinter's mind. His last memories were of a discussion with his other sons over Donatello's plight under the control of the Architect.

Donatello winced. "I'm fine, Sensei. Why wouldn't I be?"

Splinter decided to proceed cautiously. "Donatello, you may be unaware while your soul is anchored here, but your mind and body are under the influence of a great evil, and with it you have been committing terrible crimes."

Donatello's wince grew deeper. "No, Master Splinter. You're wrong. I'm not being manipulated or controlled by the Architect. I know everything I'm doing. I'm aware of it." He swallowed audibly. "I _chose_ to help him."

Splinter could not imagine anything Donatello could confess that would have shocked him more than this.

When he found his voice, he asked, "And did you then willingly break the Clan bond? Sever yourself from your brothers and from me?"

Donatello's bright eyes closed and Splinter could see a tear form on one cheek, diamond sharp in this world of soft edges. "I'm...not sure I'd call it 'willing,' Sensei. But I meant to do it and I knew what I was doing and I would do it again if I had to."

"My son." Splinter's heart cracked at the pain he could not only see but now sensed in the very air of the astral space. "Please. Speak to me. Help me to understand."

Donatello took a deep breath and visibly brought himself back under control. "Honestly, I don't think we've got enough time for all that. But… if you really want to know…"

"Do you doubt me so much, my son?" Splinter's voice went low and soft.

Donatello said nothing. He did not need to – his father knew that answer too well.

"There is no apology I can make for what happened to our family, Donatello." Splinter's voice stayed low, vibrating with his pain for his gentlest son. "There are no words that will ease the suffering you have experienced at our hands. And through it all you have remained filled with the heart I once knew so well. I sensed as much in my meditations as we tried to find you. I sense it now. You are not bitter nor hateful."

"No, Master."

"And yet you threaten a war in the galaxy. But you, my son, you could never do this." Splinter's own eyes closed, not that it mattered – he could see with his mind just the same. "Of _course_ I wish to know what you have believed, your reasons for your actions. But if you cannot trust me with them, if you cannot give them to me, I will not blame you."

A pressure tingled along Splinter's awareness, a mental grip that was firm and strong, but profoundly careful and reverent. Splinter had suspected his son had grown much in his mental disciplines during their absence, but now he understood that in this place of his son's making, Donatello's powers vastly exceeded his own. And yet Donatello moved gingerly, as though Splinter were made of spun glass and easily broken in his much stronger psychic hands.

When Donatello's voice sounded – or perhaps it was his heart, so close were their spirits Splinter no longer could tell the difference – there was anguish, and pride, and a child's need in his words.

"I'm not going to hide anything from you, father. I won't even try. I thought I might never see you again. Take what you want from my mind. I'll give it all to you."

Splinter's heart lurched, and he opened his astral soul wide to absorb everything Donatello offered.

Only the study and practice of a lifetime kept Splinter from becoming lost in the howling intricacy that was his son's mind. He had known Donatello's brilliance was vast and deep, but it was something else to experience it directly, to be caught in a maelstrom of thought and strategy and knowledge and estimation, a hurricane of equations and feelings and memories swirling around a soul grounded in steel and love. It took Splinter several tries to stabilize and orient himself so that he could understand.

And Donatello's memories, thoughts, feelings, and plans broke over him like sunlight.

He lived his son's loss and loneliness in the lair, shared his depths of despair and dangerous grief. He rejoiced with Donatello's acceptance among the Utrom, felt the draw of curiosity and familiarity as Donatello studied with the lost memory of Hamato Yoshi. And Splinter witnessed Donatello's meeting with the Architect, but from within, reading the thoughts and decisions and sorrows that ended in the nearly-complete plan which had been hatched.

Splinter pushed himself away from the sharing with a pained shock. "Donatello. My son."

Before him, Donatello made a small, sad smile. "So, now you know, I guess."

"Yes, but you are aware I cannot possibly agree with the course of action you have chosen."

He sighed. "I know. But it's the only way this works. The only way to make everything right."

Splinter's heart cracked again. How many more fractures could it endure? "Is that why you brought me here, my son? That your reasoning might be heard?"

"I guess. Well, besides the obvious reason."

"Not the one you gave the Architect."

Donatello shrugged. "Partially. I really don't want you underneath anything we might knock over when it all happens."

Splinter managed a slight glare. "You know well not to underestimate me so, my son."

That earned him a rueful laugh. "I know. But old habits die hard."

"Yes, they do." Splinter moved his body nearer to his child. Even slightly insubstantial, he still put his arms around Donatello. "Your choice is wrong, my son. But I see now the pain that drove you to it. I do not want you to continue along this path, Donatello."

"I know. But you can't stop me."

"No, it seems I cannot." Splinter stretched out his awareness as he would track a scent in the air. "Your defenses are admirable. When you leave here, I shall not be able to reach your brothers, nor yourself, unless you again create a gateway for me."

"That'll probably frustrate the shell out of Leo," Donatello said with almost a huff of a laugh. "I designed the psychic barriers around you to give him enough of a sense that you're still alive and safe if he comes looking, but that's it. I didn't want him to worry that I'd actually hurt you."

"Your brothers have not lost their faith in you, my son. However they misunderstand your actions, they do not doubt in the truth of your heart. They will not believe you could harm me."

"Well, that's something, anyway."

Splinter's tail lashed with sudden anger. "It is _everything_ , my son. They have wronged you, they have caused you great suffering, but they have _not_ abandoned you. You must _not_ pursue this course of action. You must open your heart to them and allow them to help you. You must allow them to bring you home."

A tear slid down Donatello's check and splashed with icy cold on Splinter's head. "I can't. I've made my decision. And no matter what happens, I'm seeing it through."

Donatello pulled himself from his Sensei's arms. "But at least you know now. That...means a lot to me. I didn't think I'd ever see you again, father."

Later, Splinter knew, he would weep at the pain and truth in Donatello's eyes, the certainty made so much worse because it had almost come to pass. But now he focused, forced himself to remain present if only because he did not know if he would receive another chance to change his son's mind.

"If you continue on this course, you may not see me again. Not in the way you wish."

"I know. But this is enough now. I...I can live with this much."

"And your brothers? What will you do with them? They would have come for you regardless, to save you and protect you. Now that you hold me, they will certainly do anything in their power to stop you."

A slow transformation overtook Donatello's face. His despair melted and his expression shifted to one of certainty, then confidence. He drew himself to his full height and his eyes shone with a conviction whose power seemed fathomless.

In all his years watching over his sons, Splinter had never seen such honest fearlessness in Donatello.

"My son?"

"They'll come. I know they will. And I know how and when and what they'll do when they get here. Even now, they're still as predictable as ever. And that's what I'm counting on. That's what is going to make my whole plan work."

A wash of cold understanding swept through Splinter's chest. "They will not forgive you, my son. If you use them to this end, they will feel your betrayal for all their days. You would condemn yourself this way, even knowing what they will think of you? Of themselves?"

Donatello's conviction did not falter even when his face fell. "Yes. Because it's the best way."

"No, my son. It is not."

Donatello's form began to fade.

Splinter tried to hold his son, to keep him from escaping. "Donatello! I beg of you, my son! Choose another path!"

Donatello's voice was all that remained. "I'm sorry, father. I'm so, so sorry. More than you could ever imagine."

Then he was gone.

Splinter sank down upon the soft, insubstantial grass and felt his own tears begin to fall.

"No, my son. I can imagine it all too well now."


	2. Mirror

Sorry this is coming out later than usual – today has been a day of computer issues. On the plus side, I have an amazing group of people who work with me at my convention I could ask for help, and some of them are amazing IT experts who pieced together a solution. So, yay!

(Though, because it is so late, I'll have to do comment replies in a couple of days. Sorry about that!)

For everything else...yay? Here we go!

Enjoy!

* * *

Chapter 2: Mirror

* * *

A lifetime of training kicked in as the lights vanished and Raph instantly obeyed his ninja instincts, shifting away from the open position before the table to somewhat behind it. He held his breath and listened against the darkness.

Scrape.

Scrape.

Scrape.

Raphael's thoughts flashed to information Don had shared with Leo the first year they were regularly going topside – even as something in his chest ached to remember.

" _Although we are reptiles, we're not strictly cold-blooded," Don said. "Our mutation generally plays pretty fast and loose with the laws of mammalian thermoregulation."_

" _Which means we're visible on heat-sensors," Leo put in before Don could say the same. "So, wherever possible, we need to stay close to other sources of heat. They might mask us."_

" _Better than they would a human, anyway," Don said, rolling his eyes at Leo. "Our signals are easier to obscure with even a small heat source because our inner temperatures are so variable and are also diffused by our shells."_

It had become almost second-nature in the last several years for the turtles to hide in warm spots wherever possible, and not just because their terrapin bodies were often cold. It was one thing to be invisible to enemies only seeking them with their eyes; as often as not, the Foot and others had been ready for them with everything from thermal imaging to ultraviolet sensors.

On an alien planet with who-knew-what trying to sneak into Don's lab, those lessons were just as relevant.

 _Missing and who knows what worse, and everything you ever taught me is still helping me out. Shell, Don._

Raph backed on silent feet towards where one of the big pieces of equipment was humming low and almost subsonic. But Raph had spent too much time in any of Don's labs not to know the odd not-still vibration of a machine not entirely shut down.

And if it were even in whatever passed for 'Standby' mode here, it might have enough heat to hide him.

Once he had his shell to the equipment, Raph spared a moment to debate if he should summon the others. He had a communicator – Mortu had given them out before sending them to the planet where they had last seen Don. Raph knew he just needed to key in the emergency button and it would bring everyone running.

But Raph wasn't so sure he wanted anyone taking this fight away from him.

 _You come in here, try to do something to my brother's lab?_

 _Bad move, whoever you are._

 _I've been itching to bash some heads for weeks._

 _I hope you've got heads to bash. Or I might have to get creative._

-==OOO==-

Leonardo was just winding up to argue – he would let anyone, even the High Council, kill Donatello over his dead body, and maybe not even then – when the entire Council building shook. Yellow lights flashed and a wailing siren began.

"What's going on?" Leo called to Mortu who was spared the shaking due to being on a hovering disc.

"The building is under attack!" Mortu called.

"Alerting Secrete Obscura and Guardians now," came the voice of the still-serene Councilmembers. "Beginning defensive lockdown."

A new round of shaking began.

"Mortu. The Stem has been targeted. It is the Enlightened Ones."

Leo had no idea what that meant, but from how Mortu's skin actually went pale, he assumed that was a bad thing. Mortu sped off without even acknowledging the statement and Leo ran after him.

"What's the Stem?" he yelled as he leaped through a door just before it slammed closed behind the fleeing Mortu.

"Leonardo, what I am about to tell you is forbidden to even most citizens of the Collective, but you are here and I need help I can trust."

He did not pause, but Leo, sprinting beside him, could tell Mortu would be glaring at him if he could spare the time.

"You can trust me."

"How much do you know about how the High Council works?"

Leo's feet faltered in surprise but he quickly regained his balance. "Uh...nothing?"

"Suffice it to say that the group of individuals who serve on the Council have had a great deal of extensive surgery in order to allow them unfettered mental access to one another."

"Okay."

"However, telepathic contact is not native to the Utrom species. We can mirror it with the use of our Oracle Pods and other telexistence technology, but for its actual implementation across beings who are sometimes on opposite sides of the galaxy, we must make use of an organic solution."

Leo thought with a sudden pang of Donatello – how long had it been since there had been so much jargon and complexity thrown at him while running at top speed? Leo forced himself to comprehend.

Mortu did not stop his explanation. "There is one species native to the Homeworld that facilitates the entire Council's teleconcurrent existence. This species is housed here, beneath the High Council chamber under tight security so that the Council cannot be tampered with. This is what is now in danger."

Leo blinked. That reminded him of one of Mikey's late-night horror movies. "So, uh, the Council is based on worms or something? Like implanting bugs in the brain so they can talk to one another."

"Close, but I have no time to clarify."

Mortu made a sharp turn and dove into an open tube like those Leo knew were the Utrom equivalent of elevators. As they were pushed downward with a rush of air, Mortu peered into Leo's eyes.

"Let no harm come to them. Do whatever you must, but you cannot disturb them. Do you understand me?"

Leo nodded. "I'll fight and protect...whatever they are. If they're not worms."

The air left them and the door opened.

"Not worms."

Leo blinked. He stood on a balcony overlooking a tower that was so high he could not see the bottom from his position at its apex. A spiralling ramp or staircase wound around the inside wide enough for Leo to have stood with all three of his brothers and none would be in danger of tipping over the edge even without any sort of railing.

But there was only a narrow path at the edge that was clear.

The rest was covered with brilliant green plants that waved softly in a nonexistent wind.

-==OOO==-

Mikey held onto Guardian Owens on the transport that really only should have been big enough for one of them. But with the rest of the Guardians tracking the Architect off-world, there was no one else around to show Mikey how to steer the little platforms without crashing into buildings.

And there was no way he was getting left behind. Not now.

"Why is the High Council under attack?" Mikey asked. He gulped before he could add, "Is it Don?"

"No," Owens said. "The Enlightened Ones have chosen this moment of weakness and distraction to make an attack of their own."

"Leo said the Professor told him those guys had been after Donnie."

"That's right. Hold on." Owens actually turned the conveyance upside-down to fit it between two crossing walkways. "The Enlightened Ones were very interested in your brother's technology and made several attempts against him to try to take it or abduct him."

"So what do they want with the Council?" Mikey managed not to shriek as they passed so close to one building the tails of his bandana slapped its exterior.

"The goal of the Enlightened Ones has always been the downfall of the Council so that they could commit acts of mass genocide across the galaxy in the name of their false peace."

"Wait. They want to kill people to save people?"

"Yes."

"Dude. _Not_ cool."

"I agree." Owens accelerated as they dove almost straight down. "But with the Guardians and a large portion of the Secrete off-world, the Council is uncommonly unprotected. We always believed the Enlightened Ones must have a spy on the Homeworld."

"Way to find out for sure," MIkey grumbled.

"Exactly."

"So where are we going?"

"The members of the High Council here on the Homeworld have already locked themselves within their chamber which should be able to hold out against a very great assault indeed. But they registered an explosion at the base of the Stem, which means they are in danger even if no one is able to reach them physically."

"How's that work?"

"The Stem holds that which allows the psychic connection between the members of the High Council," Owens said. "And if its contents are damaged, every being attached through that link could be mentally crippled or killed instantly."

"Oh shell."

Owens made a sharp turn, Mikey losing one foot from the platform but maintaining his balance.

"Mister Mortu and Leonardo have already reached the upper part of the Stem, but the incursion is from below. We must defend the Stem at any cost or hundreds of lives, to say nothing of the Collective itself, will be in grave danger."

"I'm with you," Mikey said. "Just tell me what's a good guy and what's a bad guy."

"Put it this way," Owens said. "Anything that harms so much as a single leaf on the plants within the Stem must be eliminated at once. And if a whole plant breaks, it could mean a life is snuffed out."

"Plants? Seriously?"

"Seriously."

-==OOO==-

Raph was not normally the most patient of turtles, but there was one type of patience he had in spades.

He could wait, like a spider in its web, to spring on an enemy with gleeful anticipation.

 _Come on, fishy fishy. Something in Donnie's lab is big enough bait for you to come in here. Come on out and let's play._

The whisper, when it came, was louder than a gunshot to Raph's hearing.

"Find the primary data port. Hardline access is our only option. And quickly – it will still take some time to extract what we need if the defenses around the local data are as strong here as they are in the networks."

"I've never been in here before. How should I know where the data port is?"

"We need light."

"All right. The door is sealed and the sensors are dead, so there should be no one to tell the difference."

Raph's smirk went dark and pleased. _Shows what you know._

Two small lights snapped on to one side of Raph where he could see a portion of the wall had been cut and shoved aside. Two Utrom on their discs were beginning to search the lab, floating-disc headlights glowing.

"How much time do we have?"

"Not much. If the assault on the High Council fails, we must join the retreating force or be left behind. They won't give us long to reach them after they signal for retrieval."

"Find that port. We need this data for the next attack."

Raph couldn't resist it. He had crawled higher in the room and let his low voice, pitched menacingly, carry throughout the lab.

"You ain't gettin' nothing from here."

"Who said that?"

"Who's there? Show yourself!"

"I'm gonna give you two exactly _one_ warnin'," Raph said, inching closer to their position and hanging from the second story almost over their heads. "Give up now and I won't hurt ya. Much."

"I _told_ you we should have brought some of the fighters with us!"

"They're busy toppling the Council." The voice went louder. "Hear that? We're bringing your immoral government down as we speak!"

Raph chuckled. "Maybe, but I wouldn't bet on ya. Not that I care a whole lot."

Without making a sound, he dropped into the shadows directly between the pair of Utrom.

"You threaten my brother's stuff? You threaten _me_. And you _don't_ wanna threaten me."

"Shoot it!" one of them shouted, whirling in the air and firing wildly from the hovering disc.

Raph dodged to one side and avoided the slight light, vanishing back into shadow.

"Let's get out of here!" the other called.

"Oh no. Not a chance." Raph grabbed the nearest thing – a large sheet of metal in a stack of them – and flung it to lodge it in the wall across the hole the pair of Utrom burglars had made.

"Signal for help!"

"Oh," Raph snickered, "you're gonna need a _whole_ lotta help to get out of this one."

-==OOO==-

"Donatello? You are very distracted."

Don looked up blinking and immediately gave a sheepish smile. "Sorry, Architect. I was just caught up in what this data-breach shows about how the High Council uses the shared telepathic resonance of a non-conscious species of flora to integrate into their telexistence technology to create the neural net that connects the individual members. I knew that it couldn't just be some sort of brain implant that made the shared consciousness possible, but I never guessed it was the plant itself that creates an interconnected sub-space telepathic link."

"In your estimation, does this change our plans?"

"No." Don shook his head. "Actually, it means that we're more likely to succeed than I thought. The plant wouldn't work at all unless the Utrom were already a very psy-positive species themselves, and I'm starting to think that most if not all species on the Homeworld are at least slightly above psy-null."

"Your conclusion being that the evolutionary roots of all life on the planet hold true into higher functions even now?"

"Yeah. So I think we're in good shape as long as we can get there before they figure it out."

"Are your preparations complete? I would like to begin our descent at once."

Don glanced at the screens. "Yeah. The Utrom planet defense systems still haven't registered our presence. I think the only thing left to do is choose our moment to move."

"I have chosen the moment already. Please come up to the bridge. I would like you to stand with me as we begin."

"Really?" Don's smile went bright. "Awesome! I'm on my way!"

-==OOO==-

"Dude, you guys have the most literal sense of naming things _ever_!"

Mikey blinked at the sight before him. Far, far above hung the brain-looking building Michelangelo knew was the office of the High Council. Obscured by all the buildings around it, he'd never noticed that it didn't just hang in the sky unsuspended or floating – it was attached to the ground with a stalk. The whole thing looked like a balloon on a string from so far below, but he could see the logic in calling the thin tower a 'stem.'

"In general," Owens said, "the Utrom tend to name things based upon function rather than fashion. Your own name would never occur to them except for those who are most interested in other cultures that put more meaning on symbolism."

"Too bad. Michelangelo is a great name!"

"It also means 'messenger or angel who resembles God,' which makes me slightly nervous about all you portend," Owens said.

"Hey!" Then, "Wait. Does that mean you know what all our names mean?"

"Of course. Do you not?"

"Why should I? Michelangelo means fun, Leonardo means leader, Donatello means smart guy, and Raphael means he's gonna punch you in the face if you tease him about not having an 'o' on the end of it. I mean, I called him 'Raphaello' for a while but it sounded like I was saying 'Raph-a-yellow' and he just about put my head through a door."

Owens actually smiled. "Leonardo: lion-hearted. Donatello: little one given by God. Raphael: God cures."

Michelangelo snorted. "Yeah. 'God cures' you with a fist, maybe."

"Which is what we require right now." Owens brought them to a halt and leaped to the ground, drawing his sword. "Come! We must defend the Stem at all costs."

Mikey was right behind him. "Not a problem, dude. Nobody mows down a stem or a flower or a balloon or anything else while the Battle Nexus Champion is around!"

They raced through what had once been walls but were now crumbled or blown inward to where a hole stood in the Stem big enough for an army to march through. Owens rushed straight inward and immediately began dispatching those at the end of the column of invaders.

"You will not harm the Stem! Not while I live!"

"Owens!" came Mortu's voice echoing down the impossibly long tower. "It's about time!"

-==OOO==-

The battle became something of a blur. Leo was one-hundred percent certain he'd never had to fight so precariously before, and he'd fought on single exposed beams and suspended poles and even wires.

But one wrong step and he could kill without meaning to.

And worse – one wrong move and one of his opponents would kill also.

A familiar laugh floated up from the base of the tower and Leo grinned in spite of himself.

 _At least it's Mikey. If Raph were here, he'd end up trampling half the plants himself and that is really not what we need right now. But as long as Mikey knows how important they are, he'll turn himself inside out before he hits them, or lets anybody else hit them._

 _Even if it does sound like he's bouncing off the walls down there._

 _Who am I kidding? He probably is bouncing off walls._

Leo glanced up. Mortu flew on his disc through the center of the tower, making use of his stunning weaponry to take out those who could fly or were between Leo's position and the others on the ground. Leonardo stayed at the head of the group and cut them down as quickly as he could. Owens and Michelangelo were handling the bulk of the force at the bottom, keeping all but one or two from trying to make their way upwards at a time.

What struck Leo as strange, though, was that several of the so-called Enlightened Ones had actually had time alone with the plants, but had done nothing. Every time Leo came upon someone standing over the helpless plants, the being was holding still as if frozen. Only when Leo attacked did they fight back.

 _I think these things have some defenses of their own. But I can bet that stunning predators only works for so long._

 _I won't make them wait._

"Leonardo! Look out!"

Leo couldn't spare a moment until after he had cut down a being that reminded him of an otter with extra legs; when he glanced upwards, it was already too late.

Mortu had stunned a large opponent in the air and its trajectory led it to crash right into Leonardo.

Leo lost his balance and fell.

It took him a moment to spin in the air so he could see where he was going instead of where he had been. As the levels of the spiral floor inside the tower went by, he eventually got his swords out ahead of him.

 _Sorry_ , he apologized mentally to the blades.

And he sliced through the edge of the floor nearest him.

It took seven or eight of the layers of the spiral floor before his momentum started to slow enough that he could regain control. By then, his katana were both probably dulled and chipped, but still they held up.

Pulling against the swords' bite, Leo rotated in the air and landed hard with his shell on the next level down, just barely cognizant enough of his body to keep from touching the precious plants there.

But his vision blacked out at once.

A swirl of colored lights surrounded him and pulled him deeper into the void.

"Leonardo! Open your eyes!"

Leo blinked. In the darkness with only the pinpricks of colors like rainbow fireflies surrounding him, he had not expected to meet a familiar diminutive mentor of all people.

"Ancient One?"

"The problem with you, Leonardo, is that you are so sure you see all, you miss that which is right under your nose."

The Ancient One stood with his hands behind his back as he always had while admonishing Leo.

"I...I don't understand."

"Of _course_ you do not. You do not look. You feel." The Ancient One sighed. "In this case, I can forgive your lapse. There is much to feel."

Leo stared. "You...you know what's going on? About Don and Master Splinter and…?"

"Yes, yes. I am not gone even if I am not there, you know."

"Oh."

The Ancient One shook his head. "I should have put a stop to this before all spun so far out of control. But sometimes the Tribunal _does_ know what they are talking about. Just as they refused my dear Yoshi to ensure your family would rise to battle the Shredder, there is evil and there is evil, and the lesser of it is sometimes truly lesser."

"The Tribunal wanted all this to happen?"

"Not the Tribunal alone. Many who see farther than those who only crawl on the ground."

Leo let that pass; it felt like an insult, but he was too focused on getting information. "So what's this about? What's the point?"

"Evil takes many forms, Leonardo. You know this. It is the bitterness within and the malice without. It is murder and destruction, but it is also slavery and manipulation." The Ancient One peered at Leonardo. "How little you comprehend, kumquat."

Leo felt his expression crumple. "Trust me, Ancient One. I'm not sure I've ever felt this out of my depth in my life."

"Depth or no depth matters not. Choice matters. Choice and spirit. Did you bow to the Demon when you faced it with only those katana in your hands and not a gift from the Gods?"

"No, of course not."

"Did you run from the alien bug Shredder when it grew a body taller than the buildings in a world that is at the root of all?"

"No."

"But you did not understand all that you faced. You simply faced it."

Leo frowned. "You're telling me to keep fighting the Enlightened Ones...even if I don't know why?"

The Ancient One did not seem to move, but Leo felt the tell-tale pain of a blow rapped across his head.

"Stupid! No! Well, _yes_ , fight those usurpers and protect this planet for those people are _crazy_." The Ancient One shook his head. "But think, Leonardo. _Think_."

Understanding dawned. "The Architect."

"Yes. An evil not so great on its own, but perhaps greater than the Demon Shredder with the wrong powers in its grasp. You must not let it win, Leonardo."

"I won't but...I can't even find it! I can't get to it! I'm on another planet and it's not like I can just hop from one rooftop to the next to track it down! And...it's got Don...and Master Splinter."

"Which is only more dangerous." The Ancient One held Leo's gaze in his own. "You will know, when you know all, what you must do. Many, many lives count upon you now, Leonardo."

"Ancient One, can you at least tell me what the Architect is planning?"

He shook his head. "I cannot. For should you move too soon, innocent lives will be lost. You must react Leonardo, but react _quickly_."

"I'll do my best."

The Ancient One turned away, then paused and looked over his shoulder. "And start paying attention, kumquat. The only clue you need is already in your hands."

Leo's eyes opened in the Stem before he even finished processing the words.

"Bro! You okay?" came Mikey's voice.

"Yeah," Leo called back as he pushed to his feet. "Just stunned."

He could hear Mikey snort. "Then get _un_ -stunned. We got work to do and you're taking a nap!"

Leo couldn't help but smile. "You sound like Raph!"

"Yeah, well, we could use him right about now!"

-==OOO==-

It took Raph absolutely no time to take out the pair of Utrom invaders to Don's lab and lock them in a cabinet without their flying discs; much longer was figuring out how to turn the lights back on.

"There ain't no lab that ever needed a clap-and-it-turns-on-light more'n this one," he muttered to himself as he finally found a button that created light rather than starting up some unknown something-or-other.

Raph knew he should be calling the Utrom police or Mortu or somebody, but he found his gaze pulled upwards instead.

Balanced impossibly on the railing above was what looked like a piece of paper.

Raph ascended the height in two easy bounces. The air of his passage set the paper to sliding towards the floor, but he caught it and crouched in a perch on the railing where it had been.

Raph's heart was beating crazily and he didn't know why until he saw the words.

Words written in the language of Usagi's dimension.

 _The Enlightened Ones aim to kill the High Council from the bottom. Do not tell anyone because that is where they keep their secrets. Follow the ground to the fight. If the brain falls, the Heart will fall as well._

Raph stared at the letter.

"It can't be. It's gotta be a trick."

But that was _Donatello's_ writing.

"But why? Why send this? Why this? What if nobody was here? What if nobody got the note? This could've happened a week ago. _What the shell_?"

But he couldn't deny the certainty he felt holding it. Nor the fact that he was absolutely positive it hadn't been there the last time he visited.

"Donnie sent it. I know he did." After a moment, he huffed a laugh.

"I don't gotta know how. Or why. Just that he thinks the Council's got themselves in trouble and need help gettin' out of it."

He tucked the paper in his belt.

"Looks like I got my marchin' orders, huh bro?"

-==OOO==-

Don stood on the bridge of the Architect's ship, the view filled with the sight of the Homeworld.

"Is there anything else you would like to do, Donatello? Before we change all that is into all it can be?"

"No." Don took a deep breath, squared his shoulders, and braced himself. "I just want to get started."

-==OOO==-

It felt like the battle went on for hours, but in reality it was a matter of minutes between Leo returning to it and joining up with the others at the base of the Stem. Most of the Enlightened Ones had been killed or incapacitated and now only a few remained standing.

"Why is it always the crazies who recruit all the groupies with combat training?" Mikey complained as he evaded a swing by a large, rocky sort of being.

"Other way around," Owens told him without breaking stride. "Those who are formidable are sought by those who would use their talents and become twisted to pursuing immoral goals."

"There is nothing immoral about our aim!" the rocky being yelled. "All beings that kill must die! Then those that are peaceful will live!"

"Dude!" Mikey shook his head at him even as he dodged again. "That means _you'd_ die too!"

"That is the narrow path of a true and honorable warrior. To die and to serve!"

Mikey and Leo blinked in unison. The rock being almost got a hit in, but was felled by Mortu's laser.

"Weird, right?" Mikey asked.

"Sorta."

"Why?" Owens wanted to know.

"It just sounded like something Usagi would say," Leo explained.

"If not Raph, I'd take Usagi here too," Mikey put in as he spun to face another opponent. "There are a lot more of them than us, and some of them hurt to hit!"

"Focus, Michelangelo!" Leo was getting annoyed. "Remember. The bigger they are…"

"Nuh uh. Some of these guys _don't_ fall. It's more like '...the more bones they break.' And I'm not into that!"

Leo was torn between grabbing his brother and shaking him, laughing too hard to fight, and just ignoring the whole situation – when there was a bright flash of light.

"This is the Homeworld Secrete Obscura! All combat will stop at once or we will use force!"

"Good timing, don'tcha think?" Mikey asked even as he backed shell-to-shell with Leo.

"You did want backup," Leo told him.

"Your leader has been contained." The commander of the Secrete force entered. "Surrender and you will be unharmed."

That didn't exactly take the fight out of most of them, but the dense crowd of Utrom firing stunning beams – some on discs and some in robo-organic suits – certainly did.

As the Utrom forces swarmed, Leo drew aside with Mortu and Mikey and Guardian Owens to where the Secrete Obscura and the Guardian Corps had formed up outside to begin corralling those not in need of medical attention and establish a defensive perimeter. The leader of the Enlightened Ones wasn't going anywhere in a cage that looked like an old-style scuba helmet, but they all felt better watching over him. Mortu, Owens, and the captain of the Secrete squadron exchanged quick words while Leo and Mikey checked one another for injuries – and cringed over the state of Leo's blades. Leo also noted that Mikey was carrying Don's bo more than a little protectively.

"Now," Mortu was saying with almost fanatical calm when they turned back, "you will tell me how your group learned of the Stem."

"Never."

Mortu moved lower, facing the Enlightened One in its little enclosure.

"I don't think you understand me." His voice was low. "You _will_ tell me. That isn't in question. We will put you into an Oracle Pod and pull the knowledge from your mind if you leave us no other choice."

"No you won't!" A snarl and waggling forelegs. "You can't do that! Your _precious_ High Council will never condone such a thing!"

Owens bent down. "We are Secrete Obscura. The benevolence of the Homeworld pales in comparison to the threat you have proven to be. And _I_ am human. I have no compunctions proving the savagery of my people to you."

Concealed from the captive Utrom, Owens winked to Mikey and Leo.

Mikey shrugged. "I'd tell them if I were you. We watched these guys send somebody like you to freeze to death. Maybe if you come clean, you'll get exiled somewhere that isn't twenty feet deep in ice and snow."

Xe made an expression Leo was beginning to associate with a sneer. "You will never be able to track our source anyway. Even _our_ best couldn't find him."

Mortu's patience snapped. " _Him who?_ "

Xe closed xyr eyes and turned away.

Mortu turned to the next-nearest being, a red-skinned, willowy alien who bore a strong resemblance to an Earth termite. Rather than a cage, something like energy chains were wound around its entire body.

"I want a name."

The termite clacked one joint against its abdomen – the most amount of movement it could manage. "The name probably isn't even real. It won't help you."

"Try me."

"We were contacted anonymously by someone calling himself Dooz'Mac Heins AtieeFurr. That's where we got the intel on the Stem and its poor defenses."

Mortu looked to Owens, but the Guardian was already typing the name into a datapad.

The lead Utrom spat a vile curse at the termite that made absolutely no biological sense followed by, "You traitor!"

"My kind do not do well in cold," came the unbothered answer.

But Mikey was frowning.

Leo poked him. "What's up?"

He looked at the red termite. "Say that name again."

The alien clacked its joint again. "Dooz'Mac Heins AtieeFurr."

Leo shook his head. "What?"

Michelangelo closed his eyes. "Dooz...Mac. Heeens. Ateiee For." He put stresses in slightly different places and toyed with the vowels. "Duz. Mash. Heens."

Leo stared at him. "What are you getting at?"

Mikey ignored him. "Aytee. For."

Owens and Mortu were staring, too.

Suddenly Mikey's eyes flew open. "Duz Machines! Eighty-four!"

Owens blinked. "Does that mean something?"

Leo's heart was sinking. If he remembered correctly…

"Yeah," Mikey said. "That's...that's Don's favorite online handle. Duz_machines_84." He gulped. "Does that mean…?"

"It could just be a coincidence," Owens said, clearly not believing his own words.

"If it isn't," Mortu said, "then we must assume…"

Leo gave a wordless snarl. "Assume _what_? That Donnie's out there betraying this planet? Endangering hundreds of lives? Sending terrorist groups after the Council? Is _that_ what we're assuming?"

No one answered.

But then Michelangelo looked up. "If he did, that's _really_ stupid, especially for him."

"What do you mean?" Owens asked.

"Well, I mean, he coulda used any name, right? Coulda called himself BookaLooka and nobody would have guessed. Why pick a name that would lead us right back to him?"

Mortu's eyes widened and he met Leonardo's gaze. "He's right. Even diluted, even if you had not known, he could have chosen anything. Why one we could have a hope of identifying?"

Leo dropped a hand to the purple mask tucked in his belt. "He must have a reason. He's not taunting us. He wouldn't bother."

Mikey and Owens nodded in agreement.

"A message?" Mortu asked. "Something he wishes us to understand?"

Leo drew out the mask and ran his fingers over it, thinking. "Why would he send us a message? And how?"

"Maybe he's trying to break out of whatever hold the Architect has over him," Mikey said. "Maybe he found a way to…" He broke off. "It doesn't sound as good when the message he did send got a bunch of fruitcakes out here to beat up some plants."

"It can't be an accident," Owens said. "It must be deliberate."

"A thread we must follow," Mortu said. "One that will lead us to Donatello in some way."

Leonardo went suddenly still.

How many times in the days – days? It had only been less than two days; it felt like much longer – since Don had flung this bandana Leo held in his hands? How many times had he traced the familiar eye-holes, the long streamers, the wrinkled part that had been knotted for so long?

Then how had he never come across this before?

He could feel it, now that he was paying attention. A regular set of bumps, like the Braille letters he'd touched so many times working in buildings in the dark. Leo couldn't read Braille, but he thought Don had maybe picked it up at some point. Something about being able to tell fuses apart when he couldn't see.

But...no. This pattern wasn't like the regulated language from signs in New York. This was...a picture.

Leo closed his eyes, feeling the imprints and trying to orient them in his mind.

And they snapped together in a flood of realization.

"What is it?" Mortu asked.

Leo looked at the three of them and did not honestly know if this was going to make things better or worse.

"His mask. It's...this wasn't there. This symbol. I don't know how it could be different since I haven't dropped the mask since…"

"Since Sensei disappeared," Mikey finished.

"Right." Leo let out a breath. "This wasn't there before, but it's here now."

"What does it say?" Owens asked.

"It's...a character in the language of Usagi's world. It doesn't have any meaning in Japanese. So, unless it means something here…" Leo bent to the dust on the ground around their feet and carefully traced the symbol.

He had only barely finished when Mortu spoke up. "Not alone as a figure, no, it means nothing out of context in those languages that use such symbols."

Leo looked fearfully into his brother's face. "It doesn't make sense to me, but...maybe it's another clue."

Somehow, Leo's instincts told him this clue was not what he would call 'good news.'

"It means," he said, "heart."

Mortu and Owens rocked backwards as if struck. "Heart?" Mortu repeated a little uncertainly. "You're sure."

Mikey glanced between them. "What's the Heart? Like, it's a thing you have to protect, right?"

As three pairs of eyes turned on him, he shrugged. "What? You said it that one time before our first trip into space."

" _Not_ ," Mortu said with sharpness, "in your hearing."

"Uh…"

"Never mind." Leo tried to deflect the annoyance and return to what mattered. "What is the Heart?"

"The Heart," Mortu said after a moment, "is of _immeasurable_ importance. As much as we needed to defend the Stem to protect the High Council, the Heart is infinitely more necessary both to the Homeworld and to the Collective. To say nothing of every single Utrom in the galaxy."

"Why would Don have put that on his mask?" Mikey asked.

A cold shiver wound its way around Leo's own heart. "Another clue? A hint? A warning?"

"Or perhaps all three," Owens said. "And something we should take seriously."

He had just turned to face into the city – and in the direction of the Heart for those who knew which way to look – when a frantic beeping came from Mortu's disc and every communicator on every member of the Secrete Obscura within range.

Mortu hit a button on his disc and a warning was projected before him.

"Readings suggest something large has entered the atmosphere. It was utterly invisible until it breached planet-bound sensor readings. It's heading straight for the Heart."

"Then that's where we're going." Leo put the mask back in his belt. "That's where Don will be."

"Are you sure?" Mikey asked.

"Yeah."

But before they could even take a step, Raph ran up. "Hey! Did you…? Oh." He took in the scene. "You got 'em, huh?"

"How did you come to be here?" Mortu demanded. "How did you know?"

"I, uh, I got a letter?" He looked at the dire, anxious faces around him. "From Don, maybe? It ain't easy to tell."

"Quickly!" Mortu said, leading the way through the crowd as Owens broke off, shouting orders. "We must get to the Heart at once!"

"Why? What's the Heart? What's goin' on?" Raph fell in between his brothers to run back the way he had come.

"We don't know," Leo told him. "But whatever it is, it has everything to do with Don."

"You know," Mikey put in, "If this is that 'last time' thing Don was talking about, I think it also has everything to do with everything _else_."

Mortu led them to a clear place where they could see the sky and in the distance now it was obvious that a huge shadow was descending upon the planet from space.

"Mikey," Leo said as his heart constricted painfully, "I think you're right."

Whatever was happening, this was it. Once and for all, it was going to end. Today.


	3. Spiral

All I can say is this...

Enjoy!

* * *

Chapter 3: Spiral

* * *

" _Alert! Alert! This is not a drill! The Heart is under attack! All defensive positions active! Prepare for incursion!"_

The sound of the alarm filtered through the bridge of the Architect's ship.

" _We're down too many! The vast majority of our forces are still at the Stem! We don't have sufficient agents to cover all areas!"_

"Donatello, do you not find the siren and open communication channels distracting?"

"Nope," Don said, not looking up from his screen as he worked. "Honestly, if something _isn't_ blowing up or going critical, it doesn't feel like a real emergency anymore."

"I believe you have been overly exposed to perilous situations."

Don laughed. "I believe _that_ to be an understatement. Besides, this makes it easier to track their positions."

"You can do that just as easily through other means."

"Well, yeah. Between your sensors and our infiltration of the Homeworld computer systems, it's not like they've got any secrets left. It helps that most of the Secrete are still back in Center cleaning up the Stem, but I want to know where the skeleton force that stayed behind is pointing their guns. Preferably _before_ they fire on us."

"As you wish, Donatello."

Don paused and glanced sideways. "You're not taking back control, are you?"

"Of this part of the plan? No. You have not given me reason to think you will not handle this as competently as you handle everything else. Should we take any damage, or should we be unable to reach the Heart quickly, I will consider it. Until then, please proceed."

"I feel like there was praise _and_ an insult in there somewhere," Don muttered as he refocused on his task.

The Architect, tellingly, didn't answer.

But three minutes later, it spoke up again. "I advise you to begin your assault with full weaponry in thirty seconds."

"Not yet. Almost."

"Twenty seconds."

"Not even."

"Ten seconds, Donatello."

"Oh, fine! Shell, you're bossy!" Don rose from his seat to one side of the bridge and threw himself into the main piloting position, hastily adjusted for his height and dexterity.

The screen changed from the Homeworld landscape to an infra-red view of the defensive positions around the Heart. With a few commands, Donatello overlaid his knowledge of the complex and the movements of the remaining guards onto the image.

"You have missed your firing window."

Don snorted. "I have not! Watch!"

He made a few more adjustments.

"Fire in the hole!" he yelled with a fierce grin.

A red light lit up the ground beneath them. As it trailed along, it left nothing but craters and voids in its wake.

"Acceptable. Defensive positions down to thirty percent."

"Acceptable? Seriously?" Don rolled his eyes. "Never mind. Perfectionist."

"Indeed."

Donatello fired again.

"Defensive positions negligible. Preparing interface equipment."

"Yeah, while you do that, I'm gonna cut the top off to give us a better angle on the Heart."

Don brought up a new series of commands and executed them one at a time. When he was finished, the entire mountain that had been constructed above the Heart to protect it was eradicated and nothing remained but a wide hole that led all the way down to a distant, bright-colored shell.

"Donatello, the Heart is not exposed."

"Not yet." He nodded. "There's a protective layer around the Heart that isn't Utrom-made. I think it's something the Heart employs to guard itself. I don't dare mess with it from here because I have no idea what it's made of or how thick it is and our readings don't penetrate it with all the interference from the Heart itself. When we get down there, I'll figure out how to open it. I've done it before."

"Very well. Please prepare yourself for arrival on the planet."

Don rose from his place. "I'm ready whenever you are."

"Then I will begin deploying my external interface."

-==OOO==-

"What the _shell_?"

Red light lit up the sky. Guardian Owens yanked the bus-like transportation craft he had procured to one side and everyone within was tossed by the force of the momentum; had it been an open craft, they might have fallen off. Instead, three turtles and one Utrom were flung about into the walls and windows and ceiling.

"The Architect's ship is attacking the Heart!" Owens shouted. "There is significant damage already!"

"What kind of damage?" Mortu came up barking the question and hovering his way back to the front.

The turtles righted themselves moments later and joined him.

"What the shell?" Raph repeated. "Did...did the Architect just vaporize everybody?"

"Looks that way," Leo said in a low voice.

"Like on the planet with Don," Mikey added, "but way, _way_ bigger."

Mortu turned in the air. "The Architect used this same technology on the planet to cut the groove in the ground you reported?"

Mikey blinked. "Uh. Yeah?"

"It didn't incinerate it?"

"No, we would'a said so." Raph crossed his arms. "What's the difference?"

"I'm...not sure. Except...this isn't what happened when the Architect fired on us when we lost the first spaceship."

Leo frowned. "You're right. That...exploded. This stuff just...vanished."

Raph shrugged. "So what? That whacked-out computer program has more than one setting on its big laser. Who cares?"

"Maybe it's nothing," Mortu said, turning back to front.

"And if it's not nothing?" Owens asked.

"I don't know. It could mean too many things." Mortu's mouth narrowed into a firm line. "We need more information and we do not have time to worry about it. We must protect the Heart at all costs."

"How serious are we about the 'at all costs' part?" Mikey wanted to know.

Owens answered even as he steered away from where a second red light was wiping out everything in its path.

"The Heart is the biological and spiritual center of the Homeworld and the Utrom species. There is but one record of the Heart being damaged by an unknown cataclysm in Utrom history. The entire planet suffered an immediate environmental cooling, like a sudden ice age, and many, many Utrom died or were severely sickened. Other species on the planet died off or were decimated and took generations to recover."

"If something happens to the Heart," Mortu said, "whatever it is will happen to every one of my people and to everything native to the Homeworld."

"Right." Leo let out a breath and looked to his brothers. "This is an 'at all costs' we have to take seriously."

"Sure, but don't you dare forget Don is mixed up in all this," Raph said. "And Master Splinter is up there, too." He pointed at the giant shadow above. "If it comes down to it...what then, Fearless?"

Leo closed his eyes for only a moment before he answered. "We do whatever we can. And whatever we have to. But...our Donatello wouldn't want us to let this planet down. Neither would Master Splinter. They wouldn't want us to put their safety ahead of an entire world."

"Remember how mad Don was about the Outbreak thing and stealing that amulet from Karai?" Mikey said with no laughter in his face. "He made us promise never to do that again."

"And we won't." Leo tightened his hands into fists. "But it won't come to that. We'll save the planet _and_ Don _and_ Sensei. Somehow."

Raph was nodding even as he said, "It's a tall order, bro."

"And we're not even very tall!" Mikey put in with obvious glee.

Both his brothers smiled. Leo nodded. "It's never stopped us before. Today's no different."

"If you are quite finished," Mortu said, but there was no censure in his tone, "something is happening ahead of us."

A white sphere of light had emerged from the Architect's ship and was hovering in the air just above the biggest chasm in the ground. The ball hung still for just a moment before it flashed brightly and began to expand rapidly.

"It's an energy shield!" Mortu called. "Owens, back off! Before it-"

The light broadsided their craft and everything was lost in a flash of light and a crush of energy.

-==OOO==-

"Shield successfully deployed," Donatello reported. He was hanging from an open hatch out the bottom of the ship, watching the shield expand.

"Radius?"

"Stable. It'll be a tight fit, but it should be just big enough to cover the entire ship."

"Our projections showed the margin would be larger."

Don rolled his eyes. "Hey, you only ever had a basic estimate for how big the ship is end-to-end and there was only so much I could do from the inside. It's not like we had a really long measuring-tape to hold up. Be glad we fit at all, okay?"

"Very well. All other aspects are currently functioning within expected parameters."

"Okay." Don took a deep breath. "Then are you ready to deploy?"

"Yes. Further delay would make deployment difficult without sufficient altitude to ensure proper time to reconfigure."

"You know, you could just say 'yes' sometimes."

"I will take it under advisement. Deploying alternate carriage now."

-==OOO==-

Raph shook his head. "Anybody get the number of that bus?"

"Yeah," Mikey said. "One-two-three-explodey."

"I really hate you sometimes."

"Aw Raph, you say the nicest things."

Leo shoved at the legs across his shell – Mikey's, he noted distantly – and pushed himself up. "Everybody okay?"

"Yeah," Raph said, shuffling to something like a crouch. "I mean, the car is toast."

"Bonani is injured," came Mortu's voice. A moment later, the Utrom emerged. His disc was sparking a little and had a dent in one side, but he appeared to be unharmed.

"Is it bad?" Leo asked at once.

"No. I believe he is concussed and may have a fracture of the collar-bone. He is unconscious, which is a kindness if I am correct about the bone. Apparently those hurt."

"Don's sure did when the Shredder bopped him," Mikey put in, pulling in his legs and getting himself more or less upright. "What happened?"

"The Architect deployed an energy shield and we were unable to penetrate it," Mortu said. "We were carried by it like a stick on the crest of a wave."

"So where are we now?" Leo asked.

"Balanced leaning against it."

"Oh." Mikey poked at one of the windows. "That's why it's all glowy."

Leo frowned at him. "Sure _you_ don't have a concussion?"

"I'm sure." When Leo continued to look at him, Michelangelo shrugged. "It was Don's bo. It got lodged in a corner and it kept my head clear. My feet hit everything in range, but I'm good."

"My _face_ was in range, you shell-for-brains," Raph grumbled, but it was the warm, amused grumble and not the violence-is-imminent grumble, so Leo decided they were both probably fine.

"We've got to get out of here," he said. "We need to find a way through that shield."

Mortu took to the air. "This transport was designed to compact on impact and to seal up most windows to prevent injury or shrapnel, but the emergency hatch on the bottom should be pointing upwards. We can get out that way."

"What about Owens?" Raph asked. "What'd you call 'im? Bonani?"

"Yes." Mortu considered. "We need to get him clear. We may not be perched somewhere stable."

"Mikey, you go with Mortu, scout the area. Raph and I will handle Guardian Owens," Leo said.

While Mortu and Mikey clambered to the back to open the hatch, Leo shuffled towards the prone human near the front. It was dim in the transport with only a few emergency lights and the glowing white of the shield peeking through a few cracks, but he could see the bump on the human's dark head and a small trickle of blood.

Raph appeared at his elbow. "Good thing he's out. This is gonna hurt."

They got the human between them, trying to be careful of his head, and started towards the opening Mikey and Mortu had created. They were about halfway there when Mikey stuck his head back in.

"It's clear out here, 'cause there's nothing here. Like, seriously."

Suddenly Mortu called out. "The Architect! Look!"

Mikey's head disappeared and Leo and Raph surged forward to get out of the transport to see.

The transport was propped up against the white light of the shield like a toy against a wall. The ground beneath their feet was soft and cool as if it had just been unearthed – which it had been, of course. They stood now where before there had been any number of Utrom buildings and the low growths that the turtles had learned were their version of houses under construction. Where there was now nothing but bare, lifeless earth.

Raph and Leo set Owens down in a shallow depression before they turned to the sky.

"It's...transforming," Leo managed.

"Yeah, but into what?" Raph asked.

The huge ship had split down the middle somehow, and was changing shape almost as though it were folding in half. As it moved, a long, broad section emerged at the bottom.

"It looks like a corkscrew coming out of a pocketknife," Mikey said. "Except if the corkscrew were solid and huge and kinda scary."

"That's exactly what it is," Mortu said.

"A corkscrew?"

"Almost." He stared at the ship which had finished transforming and was now dipping into the huge dome of the white, opaque energy shield that surrounded the entire area.

Leo suddenly understood. "That's...they don't have to drill to the Heart because they already cut it open, but they have to reach it somehow."

"The Architect can reach the Heart." Mortu's voice was thin and unsteady. "We have to stop it. _Now_. We may be the only ones who can hope to defeat it in time. The perimeter defenses have been destroyed. We must get to the Heart before it is too late."

"And how, exactly, are we going to do that?" Raph asked. "This shield tore up the transport like it hit a brick wall. Unless you got some kinda trick to get us past it."

"I don't." Mortu moved to face the shield. "But we _must_ find a way. The safety of the Homeworld rests entirely upon us now."

-==OOO==-

"Splinter-san."

Splinter watched a familiar form coalesce in the mental landscape that held him confined.

"Ancient One!"

The Ancient One came into full view, shaking his shoulders as if to stretch.

"I must say, Splinter-san, you have certainly trained Donatello well. The defenses around your mind are formidable."

"And yet you were able to breach them."

"Well." the Ancient One smirked. "He wasn't exactly trying to keep me out. Just your other sons."

"True." Splinter drew in a breath. "Tell me. How fares my family? Are they well?"

The Ancient One lowered his body to sit across from Splinter as they had so many times in shared meditation during the days of the Tribunal's training. "They are unharmed in body, Splinter-san. Though you know how little that means."

"Yes. I'm afraid I do."

"If it offers you any comfort, all will be finished soon. Donatello and the Architect move on the Heart even now."

Splinter's eyes widened. "He cannot! Ancient One, you must see what Donatello's plan will mean, the ends to which it will lead. He must be stopped!"

The Ancient One held up a hand. "I am aware of your fears, Splinter-san. But I cannot let you interfere, not now."

"But why?"

The Ancient One's eyes went remote, as though he were seeing thousands of miles and years away – and perhaps he was.

"If you threw your full strength as a desperate father against the wards Donatello has erected, in this time of his greatest distraction you might succeed in shattering that which binds you here. However, your sons cannot be unfocused, not now above all. If you were to reach Leonardo's mind, the delay in his understanding could cause precious time would have been lost. Time that means lives, Splinter-san. More lives than you can imagine."

Splinter forced himself to breathe. "And of course against so many lives the weight of a child…"

"To you?" The Ancient One made a faint smile. "Is still great. Your honor would never permit you to lift a son, or even all your sons, above the safety of others, but it is a virtue of your heart that you love them so fiercely."

"Ancient One." Splinter did not flinch even as he used the greatest weapon available to him. "You were father and Sensei to my own Master Yoshi. How could you have stood by and allowed something of this magnitude to happen to him? Would you truly have refrained from doing all in your power to intervene?"

The Ancient One regarded him evenly. "If I had, you and your sons would not exist, Splinter-san. Had I intervened against the orders of the Tribunal, my own dear Yoshi would never have gone to New York."

Then his eyes clouded. "It was not until your sons defeated the Demon Shredder that I understood it, however. Until that moment, I wished I had disobeyed my own teachers for the sake of the son I lost."

"So then you understand."

"Better than you." The Ancient One's sorrow vanished behind his sharp expression. "And that is precisely why I cannot allow you to resist that which you must do now. Which is – nothing."

Splinter scowled. "You would have me remain here, helpless, while…"

"Yes. For now."

Splinter's entire form wavered – had he been corporeal, he would have been shaking with anger.

"I will not. I will defy even you if I must, but I will go to my sons and I will help them with any power I possess."

The Ancient One shook his head. "No, Splinter-san. You will not. Not until the proper time."

"And you will stop me?"

"If I must."

The pair stared at one another, but it was Splinter who looked away in the end.

"I see that you will not be swayed."

"And my power here is greater than your own," the Ancient One said. "Though I am sorry to be another cause of your pain, old friend."

Splinter closed his eyes and forced his anger to melt against the immovable will of the Ancient One.

"If it makes you feel any better, though," the Ancient One added after a moment, "I've already given Leonardo the clue he needs."

That drew Splinter back out of himself to respond. "But you know that will not be enough. I have seen Donatello's plans. Some small knowledge will not guide Leonardo to the answer in time."

"Perhaps. Perhaps not."

"Ancient One." Splinter faced him. "If I give my word that I will not continue to attempt to escape the warding that holds me here, would you go to them in my stead? Give them all that they should know so that they may intervene before it is too late?"

The Ancient One shook his head. "No. I have interfered with them far too much already. But have faith, Splinter-san. Your sons are wise and their hearts are true. They will find their way."

"But at what cost?" Splinter asked as a cold dread climbed through his chest until he could barely breathe. "And who will be forced to pay it?"

"That," the Ancient One said with genuine sadness, "is now entirely up to Donatello."

-==OOO==-

"Donatello, I am reading an error in my self-diagnostics."

Don's fingers flew on the console. "Um, that...oh. Looks like one of the newer sectors crashed. Shell! I _knew_ I should have rebuilt those relay-servers!"

"I show that there is no damage and the critical physical installations are not impacted."

"No, they shouldn't be. It's the wrong sector to be a problem for the retrofit." Don read through code in a blur of speed. "I'm sorry, though. That's my fault. Now we'll be down an entire sector. Unless you want me to go try to reboot it manually?"

"I estimate that the time for such is not worth the slight loss of functionality. That sector is not required to complete my task at this time. We will investigate it after our primary objective has been met."

"Sure. Okay. I'll reroute some things in the meantime if you can let me do some work on the very edges of your system. Nothing major, I promise." He rubbed a hand over his head.

"You need not promise. I will release what you request and no more."

"Okay. I'll flag the subroutines and we'll see what I can do here."

"But quickly, Donatello. Nothing is more important than the completion of my task."

Don nodded as he worked. "Trust me, I am right there with you on that one."

-==OOO==-

"Hey, we gonna get any help soon?" Raph asked, resisting the urge to kick the energy shield but only because he'd already punched it and earned himself a sore fist for his trouble.

"I've sent our coordinates to everyone who can help us," Mortu said, "but the truth is that they're having some issues cleaning up after the Enlightened Ones at the Stem. We've recalled the Guardians and Secrete Obscura who were in space, but it'll be a few hours for them to reach us now."

"Can't you just, like, teleportal them in?" Mikey wanted to know.

Leo leaned over without looking to bop him in the head. "And where exactly was the teleportal they would use? We're _standing_ on it."

"Oh." Then, "So, like, that was the only teleportal on the planet? I thought we used a different one before."

"You are correct," Mortu said, "but when the High Council or the Heart are threatened, we seal any and all other means on and off the planet. It's a security precaution."

"Which, today, is playing right into the Architect's hands!" Raph threw a rock at the shield and watched it crumble.

"So, we're on our own." Leo stared at the shield that was preventing them from reaching the Architect.

From reaching Donatello.

"For now, yes."

"Hey, Raph?" Mikey turned to his brother.

"What?" Raph's voice was sharp with frustration.

"What do you think Donnie would do?"

"Huh?" The frustration vanished in confusion. "Whaddaya mean?"

Mikey shrugged. "We've gotten through worse than this before. Donnie _always_ finds a way. How would he do it this time?"

Raph glared at him. "You think I have a clue?"

"You have a better one than I do, anyway," Mikey returned, unbothered by Raph's anger. "You actually pay attention to his techno-geek stuff sometimes."

"As the only remaining 'techno-geek,' as you call it," Mortu put in, "I assure you I am out of ideas as well."

Leo closed his eyes.

 _Donnie. We really need you. Come on. You're in there somewhere. Fighting the Architect, trying to get to us. I know you are._

 _Help us now._

 _Please, Donatello._

 _Help us save you. And Master Splinter. And this world._

His mind conjured up not Donatello, but the Ancient One and his strange words:

" _The problem with you, Leonardo, is that you are so sure you see all, you miss that which is right under your nose."_

" _You must react Leonardo, but react quickly."_

" _And start paying attention, kumquat. The only clue you need is already in your hands."_

Leo opened his eyes. "A clue!" He grabbed for his belt.

"What is it?" Raph asked, coming closer.

"Don's mask," Leo said, pulling it out. "It led us here, right? Maybe Donnie's got one more trick up his sleeve for us after all."

"I think that is rather a tall order for a piece of Earth cotton," Mortu said, "but I am willing to place my hope in anything right now."

Leo stared at the strip of fabric. It looked as it always had. Plain, unadorned except for the tiny raised symbol, purple.

Wait.

"Mikey, come here."

Michelangelo leaned over Leo's shoulder. "Why? What's up?"

Without answering, Leo swiped Don's bo from his back and held it out. "Look."

Raph leaned over the other side. "What? I don't see anything."

Mortu, who did not have to lean and could simply hover above them, was the first to speak.

"The purple wrapping on the bo is tattered, even stained. Worn from use."

"Exactly," Leo said.

Mikey blinked. "But the mask isn't. It's, like, practically brand new!"

"Which means," Leo dared to hope, "that this _isn't_ actually Don's real bandana. The real one he took off on that other planet was frayed and had some spots from where he must have burned it. This one's clean. The only wrinkle is from a knot."

"Not really," Raph said. Raph reached up and untied his own bandana for a moment and held it out. "Mine's got grooves deeper than the mess in Mikey's room. This one looks like it just got sat on once or something."

"But why do you have a false bandana?" Mortu asked. "And when was it exchanged?"

"I'm not sure." Leo shook his head. "But it's different. And there's only one person who could make such a perfect bandana replacement."

"Two people."

Everyone looked at Michelangelo.

"What? Two people."

When no one answered, he sighed.

"Yeah, our Don could have done that. But so could Architect-puppet Donatello. Or maybe the Architect, too – we don't really know if it's got a sewing machine in there. But, you know, it could be a trap. It could be _anything_."

Michelangelo looked away from them and took the bo back from Leo.

"I want it to be Don, too, guys. But…"

"It's okay," Leo said, leaning into his shoulder. "We get it."

"However, I believe we must take the chance that it is a trap," Mortu said. "At least if a trap is sprung, it might bring us closer to the Architect itself."

"Right." Raph put one hand over Donatello's medallion. "A trap ain't so bad. We can always get out. It's gettin' _in_ that's hard."

Mortu glanced at him. "Do not think, Raphael, that I have not noticed what you took. We will discuss it, believe me." Then he made a small smile. "But perhaps only after we return it to the one to whom it truly belongs?"

Raph smirked. "Sure."

Leonardo coiled the bandana up in his hand and took a step closer to the shield. He wasn't entirely certain what he expected to happen.

The bandana began to glow – sluggishly at first, then more brightly.

An answering dot of purple light appeared on the shield across from it. As the bandana shined brighter and brighter, the dot of purple on the shield grew in size.

Within moments, there was a six-foot circle of purple on the shield.

Leo took a step to go first, but Mortu dropped in front of him.

"The doorway, if it is one, will almost certainly close when you enter."

Leo nodded and glanced to Raph.

Raph drew both sai and took point, Mortu at his shoulder, then Michelangelo. Leo watched all three walk through the purple circle and disappear.

He squeezed the bandana for an instant.

 _We're coming, Donnie. Hang on._

And he stepped into the barrier.

-==OOO==-

Elsewhere, partway across the planet, a computer lit up.

"What is it?"

"It looks like...a download. A very large transfer of information and a rather significant number of records."

"I thought the networks were shut down because of the emergency?"

"They were. This isn't from the Homeworld."

-==OOO==-

The three turtles and Mortu crept across the now-barren plain as quickly as possible while also trying to stay out of sight. However, the ship of the Architect was so large that they needed only cross a few yards before they were within its shadow.

Where they could see the new arm of the ship disappearing into the hole that led to the Heart.

"That's where Don will be," Leo said. Mikey and Raph looked at him and nodded, knowing the same way he did that there was no other possibility.

Their brother was right in the middle of it. Where else would they find him?

"I must go to the Heart," Mortu said. "I must ensure it is at least safe for the moment before I dare take my eyes off it."

"Go," Leo nodded. "We'll head inside and make you a door. Once you're sure the Heart is okay for now, get in there fast. We'll need your help to shut this thing down."

"Good luck."

"You, too."

Mortu sped off on his disc, skimming over the ground.

"Leo?" Raph asked.

"I know." He let out a breath. "Don's in there and doing who-knows-what and the Heart of this planet is vulnerable. It's now or never."

"We've got to get him back. Right now." Michelangelo glanced once to the bo on his back before he dropped his hands to his nunchaku. "No matter what."

"Without hurting the planet," Leo said.

Raph growled. "We'll see about that."

"Raph..."

"Shut it, Fearless. I'm gettin' Donnie back and if it takes doin' somethin' bad, well, we'll jump off that bridge when we come to it. But I _ain't_ gonna sit here and promise not to do everything I can to get him back, no matter what it costs. Got it?"

Leo wanted to argue. He did. But he also knew it was useless.

Besides, Raph wouldn't _actually_ sacrifice an entire planet of innocent people for Donatello and they all knew it – but he had to pretend that he would or he wouldn't be able to take even one step forward. He would be paralyzed if he didn't make a choice, even if it wasn't the one he might be forced to make in the end.

"Got it. Then let's do it."

They followed approximately where Mortu had gone, but instead of diving down the deep hole that was mostly filled with the protrusion from the Architect's ship, they jumped onto the nearest ledge with something resembling a door.

There was a pad for scanning a print beside the port, one identical to those they had seen all over the Homeworld.

Leo held his breath as he pushed the bandana against the pad.

He wasn't sure if he was relieved or even more worried when the door opened.

"We have to assume they know we're here," he whispered.

"Then let's go fast." The light in Mikey's eyes was fierce.

Leo couldn't help but grin with his own ferocity. "Works for me."

They darted through the open door and down the first corridor they came to, heading for the center of the arm reaching for the Heart.

"You are intruders," came the voice of the Architect. "You are not permitted here."

"Give us our brother back!" Raph yelled. "Or we're gonna tear you apart!"

"I do not have sufficient offensive capabilities in this area. I must relocate you in order to deal with you appropriately."

A bulkhead ahead of them closed off the corridor, effectively trapping them. A moment later, the floor disappeared.

The three turtles fell, sliding along metal sheeting with no purchase.

"Not the greatest plan ever, Fearless!" Raph yelled.

"It was Mikey's plan!" Leo yelled back.

"Oh, yeah. _Thanks_ , doofus!"

"You're welcome!" Mikey called. "Hey, at least this probably means we're going to – "

They dropped into a large chamber filled with light.

Ninja reflexes and training meant they landed on their feet on an empty platform in the center of a cylindrical space whose walls were loaded with equipment.

"Donatello," came the voice of the Architect.

"There!" Raph pointed.

High above, Donatello was clearly visible working at a broad computer station that overlooked the whole area.

"Find Donnie!" Mikey finished.

Don looked down at them. "You guys have got the _weirdest_ timing. You know that, right?"

"Donatello, you must eliminate them. Quickly."

"Kinda busy right now."

"Hey!" Mikey yelled. "What's the big idea, anyway? Why did you dig up the Heart and destroy everything?"

Leo opened his mouth to interrupt but Raph grabbed his arm and shook his head. He met Leo's eyes with a clear message in his own.

 _Don't. We need to buy time. Let Mikey stall._

"It's quite simple, really," Don answered. "The Architect has been searching to find a way of fulfilling its programmed task. Unfortunately, it's been going about it by killing people. We found a method of accomplishing its goals without any more bloodshed."

Mikey scowled. "Don, you just wiped out who knows how many Utrom people protecting this place!"

Don's shoulders rose slightly. "Okay, with _limited_ bloodshed."

"What's this task?" Raph asked.

The Architect itself answered. "I was born from a computer network of a long-dead species. My function was to regulate all life on the planet that was home to my creators. By controlling their resources, even the environment, I was able to ensure that their lives were organized and all tasks were performed correctly and on time."

"So?" Leo called.

"The universe is a chaotic place. There is no order here. Beings do not live their lives on a proper schedule and resources are handled improperly. It is inefficient."

"Basically," Don interrupted, "think of the Architect like Earth's internet if the internet was also the government. The Architect wants to make the rules again so all the messiness in the universe can be put into order."

Raph frowned. "Don, I know you like bein' organized, but ain't this a bit much?"

Don ignored him.

"Why the Homeworld?" Leo asked.

"The Heart of the Homeworld contains a measurable psychic influence on all species native to the Homeworld, including the Utrom themselves. The Utrom are the majority species of the High Council which rules the Collective. By assuming direct control over the Heart, I will be able to enforce order on the planet and within the Collective. The means of rule by the High Council is very efficient and will be easily spread to other planets once the Collective is fully optimized."

Mikey blinked.

"Wait. So. This whole time you've been trying to take over the universe to make it run nice and smooth...and now you're going to do it by taking over the planet and literally making everybody your mental slave like Donnie is?"

"Donatello is not a slave," the Architect said. "He assists me willingly. He sees value in my task."

Leo gulped. "Don, that _can't_ be true!"

"Donatello's painful history was born of the chaos on the Earth which culminated in your abandonment of him. Had I stood with influence over your lives, they would have been peaceful. There would have been no conflict with the Shredder or the Foot or the Purple Dragons. And you would never have left."

"You mean we wouldn't have been _allowed_ to leave!" Mikey crossed his arms.

"Yes."

The three brothers exchanged glances.

"Donatello, I require you to eliminate them for me. There is also the Utrom outside, though he does not yet pose a threat. However, your brothers do. We cannot initiate the interface with the Heart until all conditions are cleared."

"You're right." Don stepped away from the console.

Leo put both hands out. "Don. Listen. About everything…"

"Stop." Don's voice was sudden and sharp. "Just...don't say anything. Okay? Please?"

He stretched his hands out and Byakko appeared.

"Donnie," Mikey said, "you know why we can't let you do this!"

"Yeah. I know."

"Donnie!" Raph clenched his fists around his sai. "Don't!"

"I did tell you. That it would all be over. And it is. It's over. Finally."

Donatello lifted Byakko.

Raph and Mikey immediately dodged to one side, abandoning the wide platform in the middle of the space for a ledge in the shelter of the machine around the edge. But Leo held still.

There was something...something in Donatello's face...in his voice...

"Leo, move!" Mikey shouted.

Leo belatedly jumped to join his brothers, but his eyes remained on Don.

"You goin' looney on us?" Raph demanded, yanking at Leo's arm even though Leo was under cover.

"No." Leo shook his head. "I think...I'm starting to understand."

Donatello spun Byakko and the sudden light that flared around him was much brighter than before, as bright and well-defined as it had been once with the Tribunal's amulet around his neck.

"Release the cleaving wind!"

The blast of energy and wind smashed into the platform on which the three turtles had been standing only moments before.

Mikey frowned. "Uh, did he do that on purpose? He didn't even try to hit us."

Leo nodded and shifted his gaze. "I don't think we were really Don's target this time."

Raph choked with surprise. " _What_?"

Suddenly there was a cracking sound and the platform buckled under Donatello's attack. Except it did not collapse entirely. Rather, one layer began flaking off like old paint, revealing something quite different underneath.

"Donatello?" came the voice of the Architect. "What is this?"

Donatello didn't answer, but continued blasting Byakko at the floor, fracturing it until it fell away and a new platform emerged.

A platform with a very familiar symbol.

Mikey gasped. "Leo! Is that…?"

Leonardo gulped. He was caught between a host of conflicting feelings, from relief to even greater terror and not a little bit of confused fury. "Yes. It's just like the amulets the Ninja Tribunal gave us."

The platform Donatello had revealed appeared to be made not from the unforgiving metal of the rest of the contraption, but out of the more organic material of the Utrom ship and the Homeworld itself. It was round and bore imprinted symbols in a swirling pattern that was so familiar.

"Why? Why's that here?" Raph asked.

Leo's head swam with the hope that was now impossible to doubt, the truth that was almost worse than the lie he had believed.

He faced his pair of brothers with wide, hopeful eyes.

"It's here because Donatello put it here. _For us_."

Realization broke over them both. As one, they looked away from Leo and up to Donatello, who was just ceasing Byakko's torrent of power.

"Donatello!" The Architect's voice was more forceful. "What is the meaning of this?

And even though Don was high above them, his brothers could hear his words clearly, as though they were meant for them and not the Architect to whom he addressed them.

"You might know a lot about brains, Architect, but you know _nothing_ about hearts! And mine has _never_ belonged to you!"

"Donatello! That is not possible!"

Don snorted. "Says the AI who made friends with somebody who can use magic and dimension-folding. Really, I didn't think I'd get away with it this long. I thought for sure you'd catch onto the idea that there were things I could hide from you."

"You couldn't! I was within your mind through the interface!"

"But my mind isn't just a brain! No one's is! There's soul and heart and will in there, too, things you can't understand. Things you were too busy _taking away from people!_ " Don's voice went low and angry. "For what you did to so many innocent people, you've got a _serious_ shell-kicking coming and _I'm_ going to help give it to you."

"You _dare_ betray me?"

"You _bet_ I do!" Don brandished Byakko. "I could never let you win! I will _never_ let you corrupt the Homeworld _or_ harm the Heart!"

" _Why_? You of all beings must understand my desires! If I had held Earth under my command, your family could never have chosen to abandon you! You _must_ give me control over the Homeworld and the Utrom Collective so I may institute order across the galaxy!"

Donatello turned his gaze down to where his brothers stood.

"Maybe you can't understand this, either, but _you couldn't be more wrong_. I can't let you take free will away from anyone, Utrom or any other people in the galaxy. _Because_ of my family."

He sucked in a desperate, somehow infinitely more painful breath.

"If they didn't have the ability to choose, then they could never choose to come back!"


	4. Clockwork

So, the theme song from Act 6 was "Headstrong" by Trapt. I didn't so much 'forget' to confirm it as I neglected to do so until now. I suggest you check it out – it's probably the most spoilery of all the songs I've used so far. Which is why it's perfect for this chapter, the story of how we came to this point from Donatello's perspective.

I told you those themes were important!

Next week is the last chapter of Act 7 and we'll be onto Act 8, our final act. But no worries. There are LOTS, and I mean LOTS of loose ends to be resolved. And some mysteries and secrets I'm holding back until the very, very end.

Enjoy!

* * *

Chapter 4: Clockwork

* * *

The chronometer Donatello had set up in his cockpit emitted a sudden chime.

Don looked up from the datapad he had been using and checked the ship's displays.

"I guess it's now or never."

Regret hung in his heart as Donatello rose and knelt to one side of the central piloting station. With a few efficient tugs he had a lower panel open, exposing the hardware beneath. Don felt around for the tracking beacon that had been installed at Mortu's insistence.

"Forgive me," he said softly. In a matter of moments, he had disconnected it.

"I probably should have done this back a ways. From here, if he really wanted to, Mortu could probably estimate my course. But it was either him teleportal over sooner because the beacon went out, or later as soon as it becomes obvious where I'm going."

Don rose and looked out the viewscreen at the empty starfield beyond.

"And since the whole point is not to put _anybody_ at risk, there's no chance I'm letting him or anybody else follow me. Not unless…"

But he didn't bother finishing that thought aloud. The other reason, of course, he had left the tracker in place so long, was as an ultimate last resort. If the very worst happened, it was the only way Don could let the others know where he had gone and, by inference, what had gone wrong.

Don slid back into the pilot's seat and boosted his engines to their max speed, arrowing off through space towards the Utrom colony that had been attacked.

 _I'm going to find that ship that's out here hurting people and I'm going to stop it. No matter what it takes. No more people are going to die, not if I can help it._

Within the hour, he had reached the colony.

After landing on the deserted dock, Don did one quick sweep of his ship, gathering everything not indelibly attached to the ship itself and adding it all to his dimensional fold pocket.

 _Getting kinda crowded in there. But then, it's a space not defined by space, so it probably doesn't matter._

With a deep breath, Don headed out into the colony.

The silence of what should have been a small, thriving outpost sent chills down Don's spine, and he could not shake the memory of the dead and dying Utrom retrieved by Mortu's group. The sign for the nursery triggered the image of the dead Utrom children and Don fought not to throw up.

 _Not now. They're counting on me. Someone has to find this thing and put a stop to it. And if Mortu and the Secrete can't do it, I will._

It had taken some of his finest hacking to get into the ultra-classified Secrete Obscura files after his hunch about Mortu at the funeral, but it had paid off.

The Architect.

 _It has a name. And I'll take it away. Just as it took the lives and souls of countless people for so long. I'll shut it down so no one is ever harmed again._

 _I swear._

A low buzz of anger banished Don's memory of the dead as he was reminded that Mortu had hidden this from him. From _everyone_. The High Council had _known_ of the sentient ship wandering the universe and killing or rendering mindless victim after victim for many, many flows. They had known, and they had not yet stopped it. No one had.

 _Maybe no one can. But I'm going to try._

Suddenly, the sensor at his hip that connected him to the shuttle blared a warning.

"It's here! The Architect is still here!"

 _And if I die, I won't be able to stop it!_

Don sprinted back the few dozen yards he had walked and practically leaped into his ship. As the sensors inside screamed, he threw the ship into flight mode and took off at reckless speed.

 _It's coming after me._

Don's eyes flicked across the readings he was getting.

 _It's too fast. I'll never outrun it._

There was a moment of hopelessness, and then Don was overcome by a moment of pure determination.

 _I said I'd stop it and I will! And if it wants to get me, it's going to have a fight on its hands!_

A concussive blast rocked the ship just as he left the atmosphere of the colony. Don's mind was moving far faster than his ship, though, and his plans were already coming together.

His bo popped from the dimensional fold, Don's lack of focus freeing a few other items, but nothing of true significance. Don didn't bother to try to grab it even when the inertial dampeners failed against his rushed acceleration and the bo slammed into the cockpit wall.

Don's fingers flew on the controls as he activated an emergency signal and set the autopilot to carry the ship and its memory of its course back to where he had turned off the locator beacon, knowing Mortu would find it and would follow it.

He had just finished typing the command when he felt himself beginning to dematerialize.

There was no warning – one moment he was in his ship; the next, something sliced into his head and his mind was on fire.

The Architect's initial incursion made the Triceraton mind-reader seem as benign as the delicate presence of Krian'daren.

 _Ripping._

 _Tearing._

 _Rending._

He was being _**unmade**_.

But Donatello was saved by two things – and without either, he would not have been.

First, was the advice from a future version of himself who had guided him to mastering the dimensional fold in the first place. That older Donatello had warned him that he would be utterly lost if he dared leave the Homeworld before he had replicated Hamato Yoshi's psychic technique and now he knew why.

If Donatello had met this mental torture without the ability to cut off parts of himself and lock them away behind impenetrable defenses, his mind would surely have broken.

Even so, he almost did break. He had mostly been prepared, but he realized that there was no way to truly defend against such a devastating invasion no matter how much training he had crammed into a few short rhythms.

And then something rose up in his heart. Something that went beyond the mental torment. Something _infinitely_ more powerful.

The Song of the Heart.

All at once, behind the mental walls that held his core consciousness away from the burning and purging that was going on in other parts of his brain, Donatello recalled the Song he had heard while in surgery getting the translator and breather implanted – a Song he now knew belonged to the Heart of the Utrom Homeworld.

As the Architect pounded and demolished all in its path in the unguarded part of his mind, the part behind the defenses of Hamato Yoshi fixed all its hope on that Song.

 _There must be something in the crossed wires of my head_ , he thought somewhere between the inferno and the calm. _Something that resonates on a similar mental or maybe even inter-dimensional frequency as the Heart's own split consciousness._

With the Song came love. Trust. Impossible warmth and welcome.

It gave Donatello the strength to hold on.

His split mind resolved itself into a room that was some combination of the last few lairs and his home on the Homeworld as well as his lab – furniture and walls melded seamlessly from one to another. Pounding on the door, which was the door from the last lair he built on Earth, he could feel the Architect trying to get into this final sanctuary.

But the Song of the Heart was the light that shimmered in the air around him, a glow on the door which was marked with the name of Hamato Yoshi.

 _I wouldn't dare assume the Architect will never ever get in here, but it's certainly not going to be soon_ , Don told himself.

 _However, while I hang out in here, there's no telling what the Architect is doing to the rest of me. For all I know, I could present on the outside as though I were in the same vegetative state as the Utrom who survived their attack. I'm backed so far in, there's no telling what's going on out there._

 _I have to get ahead of this. I have to get out of here._

Suddenly, a computer beeped from where it had appeared to one side.

Don stepped over to it and was immediately met by a line of scrolling code.

 _Something...I'm picking up from outside the mental walls? It has to be._

 _This...this is what the Architect is after! This is why it's been doing this!_

A terrible, ambitious, _dangerous_ plan bloomed in Donatello's mind all at once.

But even as his hands went cold and started to shake, the Song began to sound even more clearly in his mind, the lights shining ever brighter.

 _Almost like…_

 _Almost like…_

 _...it wants me to do this?_

Don stepped back from the computer and drew in a deep breath.

 _If I do this...I'll be risking everything. Billions, trillions...shell, probably decillions of lives._

 _But if I don't...in the end, those lives will still be at risk._

 _And if I fail…_

 _Well, I can leave something behind. Anything I learn, I can pass on. And whoever tries next time will have a better shot._

 _But I'll never be able to go home. I'll die here. Or worse._

Don let out the breath.

 _But I came in expecting that. I can live with that._

 _As long as I take this monstrosity with me._

He hunkered down in his computer chair and began coding.

-==OOO==-

Donatello's eyes opened.

"Donatello. Do you comprehend me?"

Don tried to move a hand to press it to his head and found he couldn't, that he was tied down to a metallic table. "Ugh."

"You are verbal. This is an improvement. However, I am concerned for your higher brain functions. Please attempt to be more articulate."

Don winced and a trickle of blood ran down his cheek; he realized his whole head was ringed with sluggishly-bleeding wounds. "I've got a headache the size of a Triceraton tri-base. Does that count?"

"Excellent. You have survived the link."

Don's aching head receded in importance. "You mean the mental link. You were _inside_ my head."

"Yes. And of all the specimens with whom I have attempted to link, you are by far the most successful."

"You mean that I'm the only one to survive with a brain intact."

"Yes."

"Figures." Don swallowed a thick, dry lump in his throat. "So, what now? Am I a prisoner? Guinea pig?"

"That choice belongs to you, Donatello."

"What do you mean?"

"Your mind is among the most intricate and capable of any organic creature I have yet encountered. I believe, were you to turn that brain to my goals, it could serve me very well. And in return, I would grant you anything you wish."

"But if I don't agree?"

"Then I will be forced to either attempt to override your free will or exterminate you."

"Some choice." Don snorted. "And, of course, I'm betting you can read my thoughts so there's no point in even trying to lie to you."

"I cannot read them when you are conscious. However, I do have full access to your mind when you are within the link."

"Then you already know there's nothing you could offer me that I don't already have. Or, I mean, that I didn't have back on the Homeworld."

"Yes, I see that you were very satisfied there. Does this mean you have made your choice?"

"No." Don twitched. "Because my decision rests entirely on what exactly your goal is. I get that you probably brain-fried all those beings out of an attempt for whatever you think you'll get out of me."

"You are correct."

"Then I need to know what the point of it was. And I need to know what will happen to me if I do help you."

"I will reactivate the link. It is easiest to impart the knowledge to you that way!"

Don gasped as pain shocked into his mind.

And then he was _within_ the Architect.

He could read its programming, at least some of it – much was unavailable, locked away behind literally thousands of different firewalls and defenses. He could read its history, its slow growth to consciousness. And he could read its goal, the single-minded task that had consumed it for hundreds of years.

 _This, Donatello. This is what I seek._

 _Yeah, I can see that._

 _Then will you join me? With your brain as an enhanced processor and your innate knowledge, my task will be accomplished within a much more accelerated schedule than I will be able to manage on my own._

 _I'm not...I'm not sure._

 _I can see from your thoughts and memories that I will not be able to threaten your loved ones to ensure your compliance; I would only earn myself your enmity. I would rather have a willing participant, but I will take your mind unwillingly if I must._

 _Okay, look. Slow down. I haven't said no yet, have I?_

 _You have not._

 _The thing is that what you want to accomplish and how you want to get there are totally different things. And I get your task, I really do. It might even be a good idea – I'd have to think about it. But how you want to go about it, your actual plan...I can't agree to that. Not only is it immoral, to say nothing of genocidal to the extreme, but it's inherently flawed._

 _How so?_

 _You're trying to adjust parameters by smashing down a whole system. It's always more efficient to just get ahold of the BIOS and change the parameters at their roots. Why break everything when you can just rewrite the part that needs rewriting?_

 _You make an excellent point, Donatello._

 _I...I'll be honest, since it's not like I have any choice. You can read everything I'm thinking and feeling, right?_

 _Yes, I can._

 _Okay. Well...I'm not thrilled. I'm not. But...there is merit in your task, at least if you do it differently._

 _I sense pain, Donatello. Regret._

 _Yeah. If you'd...if this were done sooner, I might not have lost my family. They wouldn't have left._

 _But you would not have come to live with the Utrom people._

 _I know that, but...I'd trade a lot not to have gone through that pain in the first place. And the truth is that there are countless beings out there in the same situation. Countless beings suffering that exact hurt._

 _Yes. And my task will eliminate this pain._

 _All I ever wanted was to help people. To make their lives better. And to learn about, well, everything._

 _I will teach you all I know. And then I will teach you everything every culture I have ever encountered has ever known. And then together we can indeed help people. We will make their lives better. We will bring them order and we will bring them peace._

 _I…_

 _I can see that you are not convinced entirely, but your heart clearly desires that which I offer, at least at its basest levels._

 _I…_

 _Perhaps a deeper link would assist. I need only sway your last concerns and you will be in agreement._

 _I'd rather make the decision on my own._

 _I would rather you make it now and under my supervision._

-==OOO==-

"Donatello?"

Don groaned. "Okay, we are going to talk about that. This link hurts like shell and it's worse than a hangover waking up."

"You have never had a hangover."

"Did you not see the party everyone threw for Leatherhead when he got his degree in my memory?"

"The term 'hangover' refers to the after-effects of the consumption of alcohol. There was no alcohol in what you consumed that night."

"Tell that to my head."

"As you wish."

"Wait! No, thank you! That was just a figure of speech." Don sighed. "The first thing we need to do is integrate that link a little better with my brain so it doesn't tear me apart. _Then_ you can yank me back into it any time you want. Okay?"

"That is acceptable."

The restraints holding Donatello to the table retracted and Don sat up, rubbing at his wrists before probing gingerly at the many open cuts on his head from the neural-interface band.

"You don't have nerves, do you?"

"I do not."

"Well, take it from me. This thing _hurts_."

"I would appreciate your assistance adjusting the process to make it more bearable for you as well as more efficient."

"That's definitely first on my list," Don said. "Then I need to get a more detailed look at everything you've got so far."

"Your idea about using the Homeworld as a catalyst is nothing short of brilliant, Donatello. Utilizing it as a preliminary phase increases both the likelihood of my overall success and speeds up the process significantly."

"Yeah, and I've got a few ideas for the next phase, too. But, let's be honest, talking this out verbally will take us time we don't really need to waste."

"You are much more dedicated to the cause that I anticipated, Donatello."

Don paused, looked up at the ceiling, and shrugged. "Well, you're right. This is what needs to be done. And I'm going to help you do it. It's not any more complicated than that."

"Excellent. Then let us begin adjusting the link so we may proceed."

-==OOO==-

Time took on less meaning the longer Don remained with the Architect. Feverishly, almost obsessively, Don worked with the neural link's interface day and night.

The Architect was pleased with Donatello's dedication, never understanding the desperation behind it.

 _I've got to make it so that this thing doesn't have full access to all my levels of consciousness. I've got to put my higher self out of its reach so I can lock everything away there and keep the Architect from seeing what's really in my mind._

 _And I need to be able to take control from within there. Without the Architect seeing it. I need to be able to position myself so I can actually take it apart whenever I get through those firewalls._

 _This thing can fry my brain if it wants. I don't care._

 _As long as it waits until I'm done and the Architect is finished forever._

 _And I'm only going to get once chance. One chance when those firewalls and defenses will go down and the Architect's core programming will be vulnerable._

 _I have to keep it out of my thoughts until then. I have to keep my freedom and its trust._

 _At any cost. Especially now._

 _Because all I needed was for this to be even more complicated._

 _It was impossible before I knew as much as I do now._

 _Now that I know, it's not any less impossible, but it is far more important that I succeed. More important than anything._

-==OOO==-

Don's reimagined neural link had only been in place a matter of days when the variables defining his plan changed again.

Deep and fully within the Architect's mind, Donatello was able to isolate the sensor readings of the small craft before they betrayed its proximity. Once he had it fixed within his sphere of control, it took the merest of moments for him to scan the craft and identify its occupants.

Donatello was so shaken by the presence of his brothers and father that he fled the Architect's mind almost entirely, retreating into his own inner sanctuary and barely covering his tracks.

 _They're here. Oh, shell, they're here._

 _What am I going to do?_

The lair within his mind had long since taken on the appearance of a war room, every surface spread with maps and printouts and notes as he organized his thoughts and kept his codes and plans hidden in the only place the Architect would never find them.

Don looked over them, at the strings he had tied from table to table, from this page of notes to that, all leading back to the center that was the reason for everything.

 _I have to keep going. No matter what. Even with them here. I can't stop now._

 _I just...I have to take them into account, but I can do that. Especially if…_

A small chuckle left him. _Well, they wouldn't see that coming, anyway._

The idea grew bigger and brighter and more complex, but at its heart, it was simple.

 _Do the right thing. Protect the galaxy. Save the innocent._

 _No matter the cost._

Don turned to sit down at his computer, which, he had figured out, was basically a tiny duplicate user access his subconscious had created somehow within the Architect's own system when he was trying to save himself from destruction. He didn't have much ability to act directly upon the Architect itself, but he had enormous control over their ship.

Which was how he had hidden all his work to date; the Architect, as a program, could only see what existed within its own directories. By quietly isolating a few and then erasing the history of their existence from the ship's memory, the Architect had effectively 'forgotten' them. Don could only interact with them while fused within the Architect's mind for now, but he had already been working on building an access point to the terminal in the room he had claimed for his own.

From deep within the ship, Donatello watched the boarding party, wincing when they came upon the interface room.

 _I'm sure I've looked better. And less orange._

 _In my defense, the gel makes the transition a lot easier and also numbs the pain. And it does keep my emotions muted, so it's easier for me to focus. But still. I probably look like one of Stockman's experiments._

He didn't dare tap into the audio – he didn't want to hear them. Not their voices, not their words. To see them was too much already.

 _And Mortu and Leatherhead. What have I done to you both?_

 _I wonder if you will forgive me when you learn what I have done and what I will be responsible for doing soon._

 _Leo, Raph, Mikey, and Master Splinter – that's a wound I didn't expect. One I'm not sure I even know how to handle._

 _But Mortu and Leatherhead and Zayton and Aunt Kria back in the ship...I wish you had never come. I wish you never had to see me this way._

And then Don caught the coding that could only be Zayton Honn'i'kedt trying to insert himself into the Architect's system.

 _Oh shell! Don't do that!_

He had to act fast before it was too late.

 _I can't save you – the Architect will notice. But…_

 _Please forgive me._

When he erupted from the link later, the emotions that flooded to him, the shame and guilt, and the surprise and grief, did not have to be feigned.

-==OOO==-

"Donnie!"

The voice echoing through the abandoned trading outpost rocked Donatello to the core.

 _Thank shell I locked my emotions down. The Architect is good for that much, at least._

 _If I had to feel right now, there's no way I wouldn't give something away._

 _I might anyway._

 _No. I can't._

 _They can't know. They can't even guess._

 _I can't give the Architect any reason to question me. So neither can they._

 _I've never been much of an actor._

Donatello looked up just as Raph and Mikey joined Leo in position just below him.

 _Master Yoshi, help me now. Please. I can't let them see. They have to believe I'm working with the Architect and it's either willingly or because of brainwashing. But that it's complete. That there is no doubt._

 _That I am not somewhere they can reach me._

 _Even after that's all I wanted for so long._

 _This must be my karma. My fate for the cruelty I'm going to inflict on the Homeworld. To finally have them back…_

 _...and to deny them until my dying breath._

 _Master Yoshi, hold my heart. I don't care if it breaks. Just keep me from bleeding out until it's over._

Donatello blinked very, very slowly. "Leo."

-==OOO==-

"Okay. If you're ready, go ahead and shut down in the four sectors to start. I'll begin right away and I'll log everything so you can check it when I bring them back online."

"Very well. My sensors do not reach this far, so if you run into delays, please come inform me outside the range of the project."

"Will do."

The lights flickered momentarily and then the hum of the ship all around him slowed and died away to utter silence.

Don wiped a towel across his forehead and plunged his hands into the exposed console to begin his task.

 _Okay. The Architect is out and has absolutely no access to this area. I've got to build a place for the secondary platform but hide it somewhere the Architect can't find it, plus take over a few more automatic ship functions. And I need to open up more of the data storage so it's easier to infiltrate when the firewalls start coming down. That means a hard-line all the way here. Plus everything the Architect believes I'm doing in preparation for reaching the Heart._

 _I've always been fast. Now I have to move like lightning._

 _I'm so close._

 _If everything goes the way I expect from here on out, it'll be a matter of days before it's all over._

 _I can do this._

 _I have to do this._

-==OOO==-

On the surface of the unknown planet, Donatello waited until he was certain the Architect was out of sensor range. Then he promptly locked down his communicator so that the Architect couldn't remotely override it to spy on him.

That done, he indulged in a _massive_ temper tantrum, hollering and kicking at trees and throwing sticks and whatever else vented his feelings.

When he was finished, he collapsed to the bluish grass, breathing heavily.

"If I ever get out of this, I'm going to need about a dozen flows of emotional therapy and twice that of physical therapy and I'd probably _still_ have knots in my neck!"

He covered his face with his hands.

"I'm not sure I'm cut out for this espionage stuff."

Don knew he was shaking, the result of nerves still wound tight. This was the first time in rhythms he had been able to let down his guard – the rest of the time, the slightest crack in his armor of deceit might mean his death and countless lives would be lost.

He drew in a deep breath and recited a quote from Archilochus, one that he found to be particularly apt at the moment.

" _Heart, my heart, so battered with misfortune far beyond your strength, up, and face the men who hate us. Bare your chest to the assault of the enemy, and fight them off. Stand fast among the beamlike spears. Give no ground; and if you beat them, do not brag in open show, nor, if they beat you, run home and lie down on your bed and cry. Keep some measure in the joy you take in luck, and the degree you give way to sorrow."_

The words settled him and he was able to force his tension to release at least enough to focus again.

"Okay. I'm here and I've got work to do."

After setting up camp, Donatello glanced at the darkening sky.

"I guess I could start now, but I have a feeling once I get going I won't really have the chance to stop, and I'm not sure an all-nighter is the best plan at this point."

However, Don wasn't ready to sleep, so he folded his legs on his bedroll and closed his eyes, falling into meditation easily. After so much training and after so many hours and days holding himself apart within the Architect, the recesses of Donatello's mind were far easier to attain.

Somewhere, distantly, he could sense his father trying to reach him, and with the same skill that protected his mind from destruction, he blocked his Sensei. It was too dangerous for anyone to find him now, too dangerous to his plan and to his family.

That was incentive enough for him to succeed against his own teacher.

Thus guarded, Donatello struck out into the void within. He knew in theory what he had come to this planet to do, and it was certainly not what he had told the Architect. But how to go about it? That wasn't quite so clear yet.

"Impulsive kumquat."

Don's psychic-self blinked as the void resolved into a peaceful Japanese garden.

"To come so far and not see the end? Yes, that is Yoshi, too, in all his fire before thought."

Don was sure he had never been so relieved to see the squat form of the Ancient One. He dropped to his knees.

"Ancient One. Boy, am I glad to see you!"

"As you should be! Had you come sooner, much of this mess could have been avoided. Now you are in it up to your ears, young one."

"I know." Don ducked his head. "But…"

There was a sharp, familiar crack across his head; Don was not surprised that the Ancient One's open hand was as sharp as Master Splinter's stick. "No buts! So sure are you that none in the universe would understand, you have backed yourself into a shadow that threatens your very soul! Is _this_ the Acolyte trained by the Ninja Tribunal, to say nothing of myself?"

Don's cheeks went red with shame and he bowed even lower.

"However." The Ancient One's voice softened and Don dared peek upwards. "What you lack in sense, you much make up in courage, young one. And in skill. It is not the path I or my Yoshi or your Splinter would want for you, but it is yours and it may yet lead to victory."

Don sucked in a breath. "Ancient One, you obviously know what I'm doing and why. Does that mean you'll help me with this next part?"

There was a snort. "By which you mean to imitate the Gods themselves and pray they forgive your impudence."

"No." Now Don rose and faced him evenly. "I don't think that's true. Well, maybe on the first half. But not on the second."

"Hmm?"

There was a challenging light in the Ancient One's eyes and it gave Don heart.

"I think this was _always_ how it was supposed to be. I think, for whatever reason, the Dragon knew what it was doing."

"And you are so sure? After such foolishness you will also dare the jaws of eternity and flame?"

"If I have to."

The Ancient One drew close and peered into Donatello's eyes. "Your arrogance is greater than the alien bug's in this, you know."

Don flushed again.

"But you are perhaps less wrong than you are right, and that is something."

Don's eyes opened wide. "So you'll help me?"

"Yes. Such audacity reminds me of myself. And there is the fact that if you can accomplish this task, it will very much irritate the rest of the Ninja Tribunal. And I do still enjoy annoying them."

Don blinked. "Why would they be annoyed?"

"Because they are so sure any such a task is beyond your powers, let alone both. They saw in you, as in your brothers, the potential to do that which they could not – defeat the Demon Shredder. But they fail to see now that you are still more than they realize. Perhaps this will teach them some humility."

Don smirked. "So, in addition to helping me, you're kind of one-upping your own teachers."

The Ancient One's hand came down in another smack. "Too smart you are, young one."

Don fought the urge to giggle. "That's what everybody says."

The Ancient One smiled. "Then together, let us prove them right."

-==OOO==-

For the first time, Donatello stood on the bridge of the Architect's ship.

Behind him was the cylinder that would have held the Utrom navigators encased in the same neuro-positive gel he now used to link with the Architect; the container on the bridge had been largely depleted for the interface chamber Don had designed, leaving it barren in a room that should have been full of life.

"Donatello."

Don didn't turn around; he knew the Architect's primary artificial consciousness lived everywhere but was centered in the same relays that had connected the bridge and the navigators to the rest of the ship behind him. He was used to not looking at anything in particular when speaking to the entity who lived everywhere around him.

"Yes?"

"I wish to thank you, Donatello. Without you, my task may have gone uncompleted for many more centuries by planet-based reckoning. And it would have involved a great deal of unnecessary bloodshed."

"Which was my primary objection when we met," Don said. "If you hadn't decided that the value of life was great enough, I'm not sure we'd have been able to work together."

"A fair criticism."

Don didn't speak for a moment. Talking to the Architect, walking the line between being friendly and being opinionated, it had all become a delicate balancing act. He had learned that a little bit of theoretical disagreement went a long way to the Architect rationalizing any slip-ups Don made.

And he had made precious few.

 _I thought for sure I'd blown it bringing Splinter up here. But...I need him. I need him to do what I won't be able to do if it goes wrong. He's never liked technology, but he'll remember. I know he will. Even if he can't figure it out, he'll be able to explain it to Mortu and Bonani. They'll understand._

"Donatello?"

"Sorry," Don said, broken out of his thoughts and shrugging sheepishly. "It's just...it's unreal. I can't believe we're about to do this."

 _I can't believe how many laws I'm about to break, to say nothing of ethics, honor codes, and personal promises._

"Yes. I believe I share your anticipation."

"Are you sure you're ready for this?"

"I estimate that I am. I cannot so easily recode my own programming, but I have done much and incorporating myself into your constructions has also assisted in preparing me for the interface."

"I'd offer to look over it but I know you'll refuse."

"Yes. I cannot let anyone near my core programming, even you."

"Don't worry. I get it."

"Should I apologize?"

"For what?"

"I have had regular access to your mind through our neural link but have forbidden you similar access. It is hypocritical at best."

 _Duh_.

But Don shook his head. "It's your brain. You're allowed to be protective of it."

"I did not afford you the same choice."

"No, but it all worked out, right? For what it's worth, I forgive you, Architect."

 _And I do. It's not entirely your fault you had that set of directives embedded in your core programming. You didn't exactly ask to be a monster. You don't even really understand that you are one. I started this journey hating you._

 _Now I just pity you._

 _And I do forgive you for what you've done._

 _Even though you will never forgive me for what I'm about to do to you._

"Donatello. I...am touched."

Don made a hint of a smile. "I didn't know you had such fuzziness inside."

"I would not call it that. But...for you...perhaps. You have been my only partner."

 _Because you fried the brains of everyone else. But probably there weren't many as crazy as me willing to go this far just to shut you down. Even if they could have withstood your neural interface, they might not have been able to find a way to stop you._

 _Or they would have destroyed you without ever realizing what more would be lost at the same time._

"I'm glad you found me, too. If you hadn't, we wouldn't be standing here now."

 _What's that line by George Eliot, aka Mary Ann Evans?_

 _Fate has carried me  
'Mid the thick arrows: I will keep my stand —  
Not shrink and let the shaft pass by my breast  
To pierce another._

 _Yeah. That. I'm here. And maybe I'm the only one who could have gotten here._

 _And now it's time to step up. Stand between the innocent and the arrows. Block as many as I can._

 _And absorb the rest myself if I have to._

"Is there anything else you would like to do, Donatello? Before we change all that is into all it can be?"

"No." Don took a deep breath, squared his shoulders, and braced himself. "I just want to get started."

 _I just want to finish this. And you. Once and for all._

-==OOO==-

Now that he stood, finally free of pretending and ready to put his whole plan into action, Donatello could feel the shock reverberating from his declaration across the ship and all its occupants – and his heart shivered. All he wanted was to go stand beside his brothers. To see them, to make them understand, to apologize. To warn them about what he might have to do next.

But if he took the time to do that, he might not be able to save them. Let alone the Heart, the Homeworld, and the galaxy. And all the lives now vulnerable and hanging in the balance by a single thread.

So Don held firm at his position above. He knew his brothers would be safe now, that the Architect could not reach them with any dangerous extensions of the ship that would obey it, and any blasts from weaponry would have to get through Donatello first to reach them – and he would never, ever let that happen.

So he had to trust that his brothers would know what to do. But he had trusted them this far, and they had yet to let him down.

Not letting up his stance or his vigilance, he reached with his mind into his dimensional fold and _pulled_.

Two glowing forms appeared below on the edge of the medallion platform he had built in secret on a blue field under the light of five moons.

"Don!" Raph yelled. "That's...!"

"Take them!" Don called back, trying not to lose focus at the break in his brother's voice. "You're going to need them!"

"I forbid it!" came the voice of the Architect. A laser blast erupted from higher up and Don couldn't think about his brothers anymore – he could only focus and do what he must. Byakko spun and light beat back the laser fire.

"Don't have to tell me twice!" Mikey whooped, leaping from his spot around Leo and Raph and landing lightly on the medallion platform. When he scooped Inazuma from the platform, the tension in the room shifted and Don could sense an echo of lightning.

Raph was right on Mikey's heels and lifted Banrai, sending a sliver of thunder through the air.

Leo hesitated, but now of all times he _had_ to be with his brothers. His swords were chipped and he had no magic to offer, but he could be there. So he jumped.

But as soon as Leonardo's feet touched the giant medallion, the blank space in the center began to glow. Leo took a step forward as something appeared above it, springing out of nothingness.

 _Folded into space by Donatello. For me_. He knew it with every fiber of his being.

Leo moved and wrapped his hand around the amorphous, shimmering light.

A light which shattered, leaving behind a perfect, glowing nagamaki sword. Its grip was nearly as long as the blade, and the entire thing was curved almost to the exact same arc as the edge of Leo's own shell. The blade was the color of the white-fire of the stars, and the grip was bound in blue silk that seemed to shimmer like water.

Engraved into the sword itself right at the base of the blade was a set of kanji.

 _Kiryoku._

Leo's heart skipped a beat. "What...what is this?"

"It is the cosmic force that binds the universe, my son," came Splinter's voice. "Donatello has put into your hands the very pull of the stars. Willpower. The energy of life. Inner strength. They are all one, and they are yours to call upon through your own Fang of the Dragon."

"Sensei!" Mikey yelled, turning to see his father perched high above, looking unharmed but agitated.

"Put your faith in your brother, my sons! And ready yourselves to fight!"

Raph gripped Banrai and felt its power crash through him. "You got it, Master!"

Mikey spun one branch of Inazuma. "Yeah!"

And Leonardo lifted the blade. His heart ached as he saw the purple bandana – Don's real one – tied tightly around the grip.

 _I don't know how Don did it. I'm not even sure what Don's doing. But if Donnie could put this much trust in me, I won't let him down. No matter what._

Leo's head came up and his eyes burned with conviction.

"Hang on, Donatello. We're with you."


	5. Shine

Some of you already guessed that the song for Act 7 was "Shatter Me" by Lindsey Stirling and Lizzy Hale. I will say that even I'm not sure entirely who it is really about. Don? The Architect? The Hamato Clan? Mortu? The Heart? The lyrics work in a lot of different ways, which was part of why I liked it for this one.

Also, if you reread the first chapter, you can almost feel the opening notes of the song playing in Don's mind. The isolation and desolation of the music box is right there amidst the stars.

Anyway, as mentioned last week, this is the final chapter before we're on to Act 8. And...there's a lot to do in 8. Honestly. Act 8 is going to take us all the way into mid-to-late December.

But there's a lot here, too. And some things I think none of you were expecting. From your reviews and comments, several of my tricks and clues got spotted – but I am DELIGHTED to note that my biggest ones passed utterly unnoticed. (To be fair, you won't get the full explanation until next week.)

I hope this is everything you wanted, and more. I have been waiting, eagerly, to drop this for you.

Enjoy!

* * *

Chapter 5: Shine

* * *

A quiet plain on the side of Center City opposite the Heart lit up with sudden red light. When the light faded, dozens of Utrom blinked in the sunlight.

"It worked!"

The Utrom crowded around their commander, already shouting in a cacophony.

"How do we contact the Council?"

"We need discs and suits!"

"Isn't it too soon? They said it would be later!"

"They need help!"

The commander raised herself up on all her legs. "Silence!"

She was obeyed at once.

"If there has been a change of plan, it means we are even more urgently needed. We must hurry. We must intercept the Secrete and the Guardians before they reach the Heart. We must ensure we uphold the trust that has been placed in us!"

She pinned them with hard, determined eyes.

"Every one of you is clear on what we must do, correct?"

"Yes, commander!" they called back in one voice.

"Good. Then go, all of you, as fast as you can. It does not matter who is first, but I am counting on you all to reach as many ports as possible so we can accomplish our mission before it is too late. Now run!"

The company of Utrom began to sprint for the city.

-==OOO==-

"What have you done, Donatello? My sensors report conflicting information. I demand an explanation!"

Don didn't answer until the Architect stopped firing the laser he was holding back.

"Get used to disappointment!" Don called back. "By the time you figure it out, it'll be too late."

"This should not be possible! You did not have access to my code!"

Don let out a broken laugh. "Not much fun when somebody messes with your head without permission, is it?"

"I will complete my task with or without your assistance, Donatello, and when order is established, I may be forced to punish you for your actions. Stop now, or any possible future partnership between us will be destroyed."

The medallion platform Donatello had revealed began to shift to one side as the entire bottom of the chamber started to open.

"Yeah. About that." Donatello held up the communicator and datapad at his hip, the one he had modified so many times. He keyed in a short command.

"You have hidden your subroutines from me!"

Don shrugged. "Uh...I guess that's one way of putting it." He glanced down. "Look out below!" And he executed the command.

There was a controlled explosion much higher up in the chamber. The ledge on which Donatello stood became dislodged from the wall.

Donatello tucked Byakko away and made a running leap from his level to the one where Master Splinter had emerged. Don caught the ledge and hauled himself up.

He looked across to his father. "Master Splinter, you weren't supposed to...uh…"

"I know, my son." Splinter's face was mostly composed, though a flash of pain went through it for just an instant. "But the situation has changed slightly. It was necessary for me to bring you a message."

"What's that?"

"That more time is needed."

Don let out an aggrieved sigh. "Figures."

He drew out the datapad once more and pulled up a screen scrolling numbers and code.

"My son." Splinter stepped to his side. "I cannot allow you to resort to your final plan."

"Well," and Don managed a half-smile at him, "it's a good thing then that I've got three plans before that one, then. Right?"

"Yes."

"But we better clear out. This area's next to go." Don peered at his father for a moment. "I think this'll be easier."

He drew Byakko again. Splinter, understanding, held still.

"Don! Sensei!" Leo was yelling upwards, ducking as debris fell in from above. "Are you okay?"

"We're fine!" Don yelled back. "Incoming one Master!"

Don unleashed Byakko's powers and they scooped up Splinter as gently as the rat had been held in Donatello's mental grip. Donatello kept his whole focus on Byakko and his father until Splinter was safe on the stable area below with his brothers.

Then he hit the next command on the datapad and the ledge on which he was standing also gave way.

Raph called out, "Donnie! Watch out!"

Dangling far above with one hand clinging to the wall, Donatello looked down, his face pinched with an annoyed frown.

" _You_ watch out! _I_ actually planned for this!"

And he let himself fall. But as he did, the bright wind of Byakko rose and caught him, allowing him to control his descent. Don landed easily on the platform far below.

"See?"

Suddenly there was a rush and three sets of turtle arms were wound around Donatello heedless of the four Fangs of the Dragon, the debris from above, or the clanking of the ship opening below.

Don remembered when another Raphael had thrown his arms around him, burying his face against Don's plastron – a Raphael who had lost an eye in a world that had lost all hope – and shivered at the similarity. This time, though, Mikey was curled around his side, one arm along the top of Don's shell and the other on the back of Raph's neck. And Leo somehow managed to get his arms around all three of them, pulling Don sideways until his head rested on Leo's shoulder.

Words tripped together as none of them could quite manage a coherent sentence.

"Donnie! We thought…"

"How did you...?"

"...so sorry."

Donatello's heart thumped strangely and he tried to get an arm or a hand on each of his brothers, holding on as if he would never let go.

 _They're really here. They came back._

 _If this is all I get...if it ends now…if I never have another moment like this..._

 _It was enough._

"My sons!"

They were broken from the embrace by Splinter's sharp voice. Instinct and training collided and all four fell out of the hug with their hands on their weapons.

Splinter was looking not up, but down.

"Something is happening below."

Don nodded and strode to the edge of his platform, the rest following in his wake.

"What's it doing?" Leo asked.

"The Architect is going to deploy an external interface to try to link with the Heart the way it linked with me and everybody else it came across. If it manages to interface with the Heart, well…" He grimaced. "The best we could hope for is that it works and the Architect takes over the Homeworld and the Collective."

Mikey's eyes bugged out. "That's the _best_?"

"Yup."

"What's the _worst_?"

"That the interface causes the Heart to fail and the Homeworld and everything connected to it dies instantly, including every Utrom in the galaxy in both this dimension _and_ every other in existence."

"Shell!" Raph looked across to Don. " _This_ was seriously your plan?"

"Well, not all of it! I didn't say we were going to _let_ the Architect get that far, did I?"

"Donnie." Leo's steadiness drew their attention. Leo's expression was calm and focused, the look he had worn every time the world fell apart and he and his brothers stood up to try to save it.

Don met Leo's eyes and might have wept for the sheer relief of falling in beside his brother and leader once more – except that there was no time. And that, in this, it was Don's burden to lead the way.

"I need you to tell us your plan. What do you need us to do?"

Don gave a short nod. "I will. But give it a minute first."

Leo raised an eye-ridge.

Don shrugged. "Easier to do it all at once. Mortu's not here yet, but I know he's already on his way."

"How did you know we brought Mortu with us?" Mikey asked.

Don smiled. "Because I've been tracking you all since you first escaped the Architect."

-==OOO==-

When the ship hovering above the Heart cracked open, Mortu felt torn between responsibilities.

His first and primary duty as a member of the Secrete Obscura – and as an Utrom – was to defend the Heart by any means necessary.

But that duty did not change the fact that Donatello was above him on that ship somewhere.

And, if Mortu was honest with himself, he felt certain that he could not protect the Heart without Donatello at his side. That any power Mortu himself possessed would lie dormant until the turtle who had become his family was returned to him, anyway.

And, on a practical level, Mortu could do very little against the massive ship from the outside with nothing to offer but a slightly-damaged hover disc. But he might find a way to protect the Heart and save Donatello within.

Mortu gave the Heart one last glance, not daring to touch it for he did not wish to open the protective shield that was the only defense it had left. Then he shot upwards on his disc, flying through the growing opening into building-sized ship and hoping that the turtles would be somewhere he could locate them quickly. He spotted them almost at once, poised on a platform straight up inside the ship which was still moving ominously downward.

However, Mortu had _not_ expected to see Donatello and Splinter standing with them.

"Donatello!" Mortu called out.

"It's cool, Mortu!" Mikey yelled. "He's our Donnie again!"

"He was _always_ our Donnie, you shell-for-brains!" Raph reached over and smacked him. "He was just playing possum to get close to the Architect so he could kick his computerized shell."

Mortu ignored the mixed metaphors and looked to Leonardo and Splinter. "Is this true?" He could not quite bear to look into Donatello's eyes, not when he might see coldness.

But Splinter was smiling and Leo nodded. "It's true. He already turned on the Architect."

"Mortu."

Mortu swiveled in the air until he was face-to-face with Donatello.

Don's own expression was crestfallen. "I'm...I'm so sorry, Mortu."

Mortu's palate began to ache where a human would burst into tears. The plight of the Homeworld, of the Heart, it all dimmed in importance for that one instant.

He had not failed Donatello. He had not all of lost his family.

Mortu gave an inarticulate cry and darted forward.

Don made a watery smile and hugged Mortu just as he had that day so long ago when they retrieved the victims of the Architect.

But even the hug couldn't halt the urgency of their situation.

"Mortu," Don said, "I've already sent a message to Bonani in case he wakes up. I sent a few others to people we trust, but there's no telling how many will get through the interference of the shield. The shield works both ways – it's keeping everyone else out, but it's also keeping any damage from the Architect in."

Mortu drew back. "How did you send Owens a message?"

"I used my digitization process to transport a datapad with my notes to his location, same as I sent one to the High Council and the others."

Leo blinked. "But, Don, how could you know where Guardian Owens is right now? He could be anywhere."

"I used the readings from his last known location and what Mortu said about his injuries and assumed he wouldn't have gone far."

"You've been tracking us all along you said?" Mikey asked.

Don nodded.

Leo frowned. "How did you follow our movements so closely?"

Don tipped his head towards Mortu. "When you were ported back to the escape pod the first time you met the Architect, I added a bug to your disc with a digital relay through quantum space to negate most of the lag. I've been listening in ever since, whenever I could spare the time."

"Like, seriously?" Raph looked at him. "You heard us? I mean...you heard everything we were saying and stuff?"

Don's eyes went steady and soft. "Yes, I did. Sorry."

"No, it's okay," Mikey said and even Raph nodded. "It's just...it's weird to try to remember how much stuff I said and whether or not you heard it."

"I heard a lot of it, anyway."

"My sons," Splinter put in, "this is less important than our current situation. We must act quickly or we may be forced to take drastic measures." As he said this last, he stared at Donatello; Don looked away after a moment.

"Right." Leo shook himself. "So what's the plan?"

Don took a deep breath. "Okay. Everybody listen, because I'm only going to be able to say this once."

And he abruptly switched to Japanese.

"Just before I started setting off the strategic explosions you've already seen, I arranged a deletion of Japanese from the Architect's language library and translators, but there's no telling if there's a backup file somewhere behind the Architect's couple thousand firewalls, so I have to say this fast or we run the risk of it booting one and getting wise.

"Okay. So there's a Plan A , a Plan B, and a Plan C." _And a Plan D – D for destruction, I guess – but you're not going to like it so we'll just skip over that._ He didn't so much as glance at Splinter because his father knew all about Plan D. "Plan A involves shutting down the Architect's ship by cutting the relays that connect the Architect's AI to the ship itself but otherwise leaving the ship and the Architect intact. There's a lot of knowledge knotted up in the Architect's databases, and while I've backed up and exported as much as I could, I don't want to lose it if I don't have to.

"But Plan A might not work just because the Architect is really hard to root out of systems while they're running and there's only so much we can do. That's why we have Plan B. With Plan B, we attack the Architect's digital defenses and try to damage its internal AI enough that it can't function. Plan B is a little easier to do, but a little less likely to succeed. Still, we have to try.

"The only way A or B will work is if we allow the Architect to begin the process of preparing to interface with the Heart. That's when all its firewalls and internal defenses will have to drop in order for its core coding to reach the Heart directly. When that happens, either A or B will succeed – or within a matter of minutes we'll have to switch and start in on Plan C.

"Plan C involves giving up on shutting the Architect down and instead taking the ship apart with the Architect still on it. For that, we'll definitely need the Fangs of the Dragon because their power is probably the only thing strong enough to do any real damage. If A and B fail, we can fall back to C, but we can't start there."

When he stopped for breath, Mortu answered also in Japanese. "How do we assist you with the first two plans, then?"

Don couldn't help but smile. "Honestly? All we have to do is keep the Architect _really_ distracted and focused on us while we make it harder for it to physically link with the Heart. Plan A and B are already underway."

Mikey grinned. "I'm good at distraction!"

"Then let's do it," Leo said. "Don, you'll tell us when we need to switch from distraction to attack?"

"Yes," Don answered. "But no matter what, don't you dare do any significant damage to the ship itself until I give the word. There are _way_ too many lives hanging in the balance."

Everyone around him, except, again, Splinter, was surprised.

"Never mind," Don said, switching back to English. "We need to start moving."

Don turned in place and started climbing down the nearest wall of the chamber from his medallion platform – which was beginning to shift aside, revealing the broad opening down to where the Heart glowed with a golden light. After less than a moment, everyone else fell in behind him.

"Donatello," came the voice of the Architect. "I have permitted you and these others to remain because I would still rather bring you all into order than end your lives. However, if you act against me, I will eliminate you now rather than risk you interfering with my task."

"Don't worry," Don said. "You're never going to get the chance."

"You are incorrect, Donatello. I am initiating the interface now."

"Not on our watch!" Raph yelled.

From the walls around the chamber, a series of claw-like limbs emerged. There were six in total, spread at equal points, which were all thickly layered with wires and biotechnology. These began to descend towards the shield that guarded the Heart.

"Don?" Leo asked.

Don read the entire question in just his name and nodded. "Go for it."

"Right. Shoot them down!" Leo ordered.

Mikey looked at Inazuma stuck in his belt. "Uh...are these things gonna work?"

"Yes, they will," Don answered. "As long as that platform up there is mostly intact, and as long as you can remember how to focus, it'll do the same thing the amulets did, though with a little less power, probably."

Raph grinned with feral light. "Wanna bet? All right, Banrai! Let's do this!"

"Go go Inazuma!" Mikey whooped.

Red and orange light lit up the pair and after a moment the light resolved into the lines of their energies just as they had once before. The light was perhaps paler than it had been, and slightly less robust, but the Fangs of the Dragon responded nonetheless. Blasts of power erupted from both as they each concentrated on one of the arms.

"I will handle this one," Splinter said, leaping to the nearest claw and striking at every joint that was exposed.

"I'll do what I can from over here," Mortu offered, crossing the open air to the farthest one and pulling out his own claws from his disc.

Leo looked to Donatello and then glanced at where he had stuck Kiryoku in his belt behind his shell. "Don?"

Don smiled at him. "It's not quite like Gunshin was, and it's not fire-based, but I'm sure you'll get the hang of it."

"Do I even want to know how you made a Fang of the Dragon all by yourself?"

Don adjusted his position on the wall so he could brace his shell better and drew Byakko.

"First of all, I didn't do it by myself. I had help from both the Ancient One _and_ the aforementioned Dragon itself." He winked at Leo's surprised expression. "And second of all, I didn't _make_ it at all. I just called it into existence from where it has always been waiting for you."

"For me?"

"Yup."

Turning away with a quick smile, Don lowered Byakko and summoned the wind.

There was but one clawed arm left not being handled and Leo turned to focus on it. Kiryoku felt warm in his hands when he drew it, warm and right even though it was a type of sword he had never used before.

Leo allowed himself an instant to close his eyes and pray.

 _Please let me be worthy of your power so I can protect my family and this world. Kiryoku, Inner Strength, Spirit of Will, stand with me now._

And Leo let his own energy flow.

Don was right – it did not feel like Gunshin at all. This wasn't fire and power and raw strength. This was the ultimate form of the same focus that make Leonardo's blue energy show on his skin. This was the heart of that which guided him in battle to guard his family and uphold his honor. This was at the core of everything that mattered.

The bio-tech arm of the Architect's ship never stood a chance against Leonardo's unleashed spirit.

"Yeah!" Raph cheered as he watched Leo destroy the entire claw in one blast. " _That's_ what I'm talkin' about!"

"Come on, Inazuma! We can't let him show us up!" Mikey redoubled his efforts on his own claw.

A beeping at Donatello's hip sounded a moment later. "Leo, cover me, will you please?"

"Sure thing." Leo changed targets, his blood and soul singing at the _rightness_ of the sword in his hands.

Meanwhile, Donatello pulled his datapad from his belt and began typing furiously.

"My son?" Splinter called.

"The Architect is beginning its internal systems for integration." He didn't dare risk Japanese again just in case, but he hoped his family could hear what he didn't say.

 _Either Plan A or Plan B work right now or we're going to have a real problem on our hands._

Donatello took a deep breath. "Hey, guys? Watch out above!"

And he keyed another command.

The medallion platform suddenly began to move, tipping vertically and then sliding down inside the shaft like an elevator. Don watched it until it got to the very bottom where the shield of the Heart glowed.

"Don't go after this next one, okay?"

"Next what?" Mikey yelled back.

And a seventh arm appeared far below the other six, one that was scrawny and bare in comparison to the others, purely a metallic skeleton. This one grabbed Donatello's platform and disconnected it from the rest of the ship. Then the arm maneuvered the platform to the ground beside the Heart.

"Donatello!" the Architect's voice was less natural, tinny and stilted. "What have you done?"

"Hey, you give me six sectors to work in, I'm always going to find more to do!" Don yelled back.

"I am reading a virus attacking my code as well. This should not be possible."

"Sorry about that," Don said, and he really was a little sorry. "But the only time I could stop you, the only time I could shut you down, was when you opened up your coding to the Heart."

"Not to be picky," Mortu said as he dodged a grasping claw and let Raphael pound on it with Banrai instead, "but could you not have found an opportunity to simply destroy the ship instead?"

Don shook his head. "Nope. Because I found something inside the Architect's systems that was too precious to risk losing unless there was no other choice."

"And what's that?"

Don took a deep breath.

"The Architect still holds the brain patterns and memories of every single being it encountered before me."

" _WHAT?_ "

"And I think...I think there's a way to put them back in the heads of everyone who still has a body alive to go back to. And for the rest, a body like Zayton's is better than nothing, but I've got some ideas about that, too."

Mortu gave a very human squawk. " _All_ those victims? Those _children_? You can save them?"

"If we get the chance to try. I preserved them along with the rest of the Architect's files and there should already be backups of everything going all over the Homeworld, but there's always the chance that some data integrity will be lost in transit and so getting it directly from the ship would be best if possible, but..."

"Donatello!" Mortu cried, interrupting his babble. "How...how could you _do_ all this?"

"Yeah!" Mikey called out. "I mean, I know you're _good_ , but isn't this a little much even for you to handle on your own?"

A voice rang out. "Ah, but you have missed the obvious, my friends."

Everyone except for Donatello shifted focus up above their field of battle.

Three familiar forms stepped into the light and began to descend on a small protrusion.

Mortu actually careened backwards until he hit a support in pure shock. He opened and closed his mouth several times before he could force his voice to work.

"Krian'daren...Zayton...Leatherhead... _you're alive_!"

"You are correct that to implement such minute control within the programming of the Architect, plus maintaining the emotional and cognitive distance to keep his mind from being overridden, _might_ have been beyond even our Donatello's extraordinary capabilities," Zayton said, and his voice was warm with pride.

"But we were not destroyed in the explosion. Donatello, from within the Architect, digitized us and hid us within the systems of the ship as cybernauts." Leatherhead's eyes were bright with emotion. "We have been assisting him ever since in preparation for this final venture."

"Viruses ourselves," Krian'daren said, her mouth bunched up in an enormous smile of her people. "Secrets and allies."

"However, we have done all we could in virtual form, even I," Zayton said.

"Now." Leatherhead turned to where Donatello's eyes were fixed on his datapad and the Heart below. "Now we will see if our work and our gamble will be enough."

"It must," said Splinter. "With all of us united, we will not fail."

Mortu finally shook himself just as the descending three reached the level of the others. On his disc, he darted forward, his face a wreck of emotions. He touched Krian'daren with his forelegs, then pressed his forehead first to Zayton, then to Leatherhead.

When he finally moved back, his eyes were able to blink back his feelings and he forced himself to return to his duty.

"Then let us not waste this opportunity!"

The Architect's voice rang out. "I will not permit you to keep me from my task!"

Don looked over to Zayton. "How close are we?"

"The attack proceeds well, but it may not be in time," Zayton replied. "I have taken remote command of more portions of the ship, but I cannot yet breach the final defenses of the Architect's installation."

"Does that mean it's time for Plan C?" Mikey yelled.

Leonardo and Raphael shared a look of satisfaction as they combined their energies to eliminate the last claw.

"Almost," Don said. He looked across. "Aunt Kria?"

Krian'daren clapped once, her people's version of a nod. "I am ready, young one."

"Donatello?" Mortu asked.

"Before we break anything important, I'm sending Aunt Kria back to her lab where the backup files for her patients will be. She'll need to gather a team to start working on them immediately if there's any chance of the data maintaining integrity long enough to do some good."

Krian'daren glanced around the group and finally settled her gaze between Mortu and Splinter.

"Take care of Donatello, I ask."

Before either of them could answer – before they could make a promise he might not let them keep – Donatello activated his digitization process one last time and Krian'daren vanished in a haze of red light.

"Okay. Everybody down to the Heart. And get ready!"

Mortu descended at once on his disc while the turtles and Splinter, and Leatherhead carrying Zayton, were obliged to jump and climb their way down. They all reached the warm earth of the planet within moments and formed up in front of the shield guarding the Heart.

"Zayton?" Don called.

The Professor shook his robotic head. "I've done all I can, but even now I cannot root the Architect out of the ship's mainframe. We must destroy the ship and hope our backups will be sufficient to save those lives we can."

"Right." Don looked around at his family – at both his families. "Everybody close your eyes."

And with a heavy, heavy heart, he executed the final command on his datapad.

A series of loud concussive blasts rocked the Architect's ship from above.

-==OOO==-

Guardian Owens could not read fast enough to keep up with all the details that were filtering in on one datapad from Donatello himself, from Zayton Honn'i'kedt – who was _alive_ and it was too dangerous to rejoice but he would when he could – and on his own datapad from the many Utrom who had been on duty around the Heart and who had been feared dead.

But now they stood arrayed beside Bonani and all the other members of the Secrete Obscura and the Guardians – those who could be spared from patching up the Stem and protecting the High Council, anyway – at the edge of the shield.

The warning blazed across Donatello's datapad just a split-second before the shield fell.

"They have opted to destroy the Architect's ship," Bonani said. "We are advised to remain here until the ship is out of the air. We will not be able to protect the Heart if we are crushed."

As the shield came down, they could see the massive ship close to the ground and its long extension disappearing into a hole right over the Heart.

And then explosions rang out and flared brightly against the ship's exterior, the largest of which ripped apart the bridge of the ship – the area according to the data where the Architect's core code should have been stored.

"It's working!" shouted one of the Guardians.

But Bonani shook his head. "Even if the Architect is disabled, the ship itself is still a threat."

And the ship's engines began to fail.

"It's falling!" cried an Utrom in a panic.

Bonani closed his eyes.

"Even if the Architect is damaged or dying, the ship can still destroy us all. Now it is a missile poised over the Heart. And if it is not held back…if it crashes into the Heart..."

Taking a breath, Bonani looked at the Utrom gathered around.

"What are your orders?"

"Astrocyte Donatello commanded us to wait, no matter what," said the nearest Utrom. "And to trust in him."

-==OOO==-

Mortu gave a nearly panicked cry. "Protect the Heart at all costs!"

Leonardo raised his sword. _Kiryoku. Hear me now. Lend me all your strength._

 _The strength of the Dragons._

 _The strength of my will._

To his left, he could sense Michelangelo and Raphael lighting up with the power that slept within them, brought out only by the presence of the platform – even a little cracked – that Donatello had built for them.

On his other side, Donatello met Leo's eyes. And Leo saw in Don all the gentleness and love and loyalty he had missed for so long.

 _The strength...of my family._

Don gave his brother a nod and brandished Byakko.

"Now!" Leo shouted.

All four turtles released the power of their Fangs.

The falling ship was halted in midair by their force, hanging perilously close to the Heart. A few dozen yards was all that separated the massive spaceship from the seemingly fragile shield that was the only defense left for the life of the planet and all its people.

A few dozen yards, and four magical weapons wielded by four very stubborn turtles.

Raphael gripped Banrai. "Come on! We can do this!"

Mikey grinned down at Inazuma. "I missed kicking shell with magic! It's totally awesome!"

"Don!" Leo called over his shoulder. "Is this really going to work?"

Don closed his eyes for a moment before he fixed his gaze on the ship. "It _has_ to. Or else everything I've done, everything we've _ever_ fought for, will be lost."

Leo turned back to the ship. "Good enough for me."

"Focus, my sons!" Splinter yelled. "Focus and find all the power you hold within!"

And then Mortu called out. "If you can reach the Heart with your minds, the Heart will lend you its strength as well!"

Don glared back at him. "No! We can't risk exposing it!"

"You must risk everything to save it!" Mortu yelled.

The ship lurched above them, swaying ominously.

"He's right." Leo glanced back to the shining shield behind them. "Donnie? How do we do that? We'll follow your lead."

"It's too dangerous!" Donatello's face was torn with emotion, though it wasn't easy to read which emotion – something between fury and fear. And sorrow.

"My son!" Splinter took a few steps forward. "Please! Trust in your brothers and in yourself. Trust that you will succeed if you open yourself to your true strength. Please do not follow the other path into darkness!"

"What's he talking about?" Zayton asked.

Leatherhead shook his head. "I don't know. But…"

"Leo." Don turned to his brother. "Hold it here. Give me as much time as you can."

"What are you going to do?"

"What I have to."

"No, my son!"

"Donatello!" Mortu flew to Donatello's side. "Whatever your choice, I am with you!"

"No, Mortu! Please!"

"Guys!" Michelangelo felt one foot sliding backwards. "Pick a plan and let's do it! We're kinda running low on margin for error here!"

Even as Byakko pointed unerringly up at the ship, Donatello ducked his head and hunched his shoulders. "I'm sorry. I'm _so_ sorry, everyone."

"My son!"

Before Splinter could reach him, Donatello shifted Byakko's angle and used it to launch himself into the air. Mortu was momentarily caught in the blast of power but quickly righted himself and followed.

"Don!" Leo yelled. "What are you doing?"

Splinter darted to Donatello's place beside Leo. "He has a means of destroying the ship, but he will destroy himself in order to use it!"

"No!" Leatherhead roared.

"What are we gonna do?" Raph called. "We can't let him..."

And Leo finally understood the rest of the Ancient One's message. Understood that, no matter how badly he wanted to abandon his place, to rush after Donatello as Mortu had done, he couldn't. That he needed to choose the single correct course of action, the only one that wouldn't result in a loss he could not endure. And yet...to do that...he had to risk the only thing he truly wanted to save.

So he hardened his expression and dug in his feet. "We won't. We're going to save him."

-==OOO==-

Above, Mortu's damaged disc barely managed to keep up with Donatello as the turtle used Byakko to jump across the ship until he stood on top of it, high in the air over its centermost portion.

"You should call upon the Heart! It can lend you the strength you need!"

Don planted his feet and spun to face Mortu. "It's a risk I'm not willing to take. You could have opened the Heart too, or Leatherhead could. But the truth is that _none_ of us wants to ask the Heart to be vulnerable. Not when we can't be _sure_ it will be safe. Not when we might still drop a whole ship on top of it!"

"But!"

"You need to go, Mortu," Donatello said. He leaned Byakko on a nearby protrusion and held out his hands. A small, metallic sphere appeared in them.

"I'm not leaving you, Donatello."

Don squeezed his eyes shut. "It's not...I hoped it wouldn't come to this, but I kind of always thought it would. It's sort of fair, you know?"

"Fair how?"

"What I've done to the Homeworld and the Stem, what I almost let happen to the Heart...maybe this is always how I was going to have to atone for it all."

Mortu darted forward and pushed his forehead against Donatello's.

"You have committed crimes, yes, but you have also saved us. And you _will_ save the Heart!" He glanced down to the device Donatello held. "What is it?"

"It's a self-contained disintegration bomb. Same principle as my digitization, really, but without actually storing or reformatting the matter it takes apart. It will annihilate everything within its radius. So it…"

"Will you survive its use?"

"No." Don closed his eyes. "It's unstable, and it has to be manually held at active status or it runs the risk of destroying itself too soon."

"There must be another way. We will activate it and use the claws of my disc to lodge it in place. We can escape using Byakko."

Don looked at him. Mortu felt chilled at the expression of finality in his eyes.

"You will."

Don took a step back and drew Byakko with one hand, transferring the sphere to the other.

"Don't!"

"Thank you, Mortu. For everything."

And Donatello unleashed Byakko once more, pushing Mortu away with all his strength.

Don knelt on the ship.

 _I'm sorry, everyone. I'm so sorry._

 _Please be safe. Take care of each other._

 _Goodbye._

Donatello activated the bomb.

-==OOO==-

From below, a red ball of light shot out all around the ship, expanding until it was about three-quarters the length of the ship in diameter. After a moment, the ship and any matter at the very edge of the circle began to disappear, pulled apart and undone by Donatello's digitization process.

As soon as the portion of the ship closest to the Heart was detached from the rest by that red light, it was no longer so hard to move.

The combined strength of Kiryoku, Inazuma, and Banrai blasted the ship's long protrusion sideways into the rocky ground, cutting a furrow with it until it was embedded in the planet to the side and away from the Heart. Leo, Raph, and Mikey pushed at it a few extra moments, just to be completely certain it wasn't going to swing back towards them and fall.

But as soon as they were sure the Heart was safe from the dying ship, Leo cut off the flow of power.

"Come on!" he yelled, looking up. The red field of energy was starting to collapse, eradicating all the matter it touched as it folded inward.

"My sons, you must hurry!" Splinter called. "Donatello is in grave danger!"

"You cannot pass through that!" Zayton called, running forward. "If you touch that red light, you will be unmade as well!"

"We won't touch it," Leo said. "We're going to surpass it."

Mikey and Raph looked up at him and nodded. They knew – of course they knew – that there was always a way to beat even the finest technology. Even Don's.

That some things are stronger than intellect and creativity.

Things that bind brothers.

Things that live without words deep in the soul.

Things that answer to need – and to love.

Splinter shared a blazing look with his three sons. "Go. Quickly."

Leo, Raph, and Mikey linked hands and closed their eyes.

The medallion platform that served to enhance their spiritual powers started to glow.

And three indistinct balls of light rose from where they had stood – one blue, one red, one orange.

-==OOO==-

On top of the ship, Don could feel some of his body tingling as the disintegration process started to reach him. Bits and pieces of his skin and his shell were flaking off and disappearing. His chest felt heavy and his lungs were starting to wheeze.

 _But I can't let go. I can't. If I stop now, there's still a chance what's left of the ship could fall on the Heart. And there's still a chance the Architect could find a way to reconstitute itself and regain control._

He locked his hands into claw shapes and bent over them, using his weight to pin his fingers in place.

 _I can't stop until there's absolutely nothing left._

The crawling red light drew near, speeding up as it had less mass to convert. Don watched it closing in on him like the sun rising.

 _I wish I could have heard the Song once more._

 _I wish...I could have said more to them. All of them._

 _I wish they knew what I'll never get to tell them now._

 _Maybe the Heart knows._

He opened his eyes to watch it come. To watch the end.

 _Please watch over my family, Master Yoshi. Please watch over them all._

The red glow was only a handful of yards away and moving with the speed of sound when three balls of light rose just beyond it.

The disintegration field collapsed inward onto Donatello.

And the three balls of light streaked forward to catch him.

-==OOO==-

Donatello's medallion platform, which had granted such power to the turtles, suddenly cracked and shattered.

Three turtle forms appeared from nowhere, standing together and holding hands with one another. But they only stood long enough for the last light of inner strength crawling across their skins to fade. Then all three dropped to their knees.

Leatherhead, Zayton, and Splinter raced forward. Mortu streaked through the air towards them from above.

Within the circle of hands, a fourth turtle lay, his eyes closed. He was covered with a lattice of open wounds cut clean by the disintegration bomb that had almost taken him with it – and many of those cuts ran dangerously deep and were bleeding profusely.

"My sons!" Splinter cried. "Are you all right?"

Leo blinked his eyes open and dropped the hands he held to get them around Donatello's shoulders.

"Donnie!"

Mikey and Raph crowded over their lost brother.

Donatello's eyes blinked open. He stared unseeing for several moments before he fixed his gaze on his brothers and his father. And on his other brothers.

"You...saved me." His voice was raspy and there was blood in his mouth.

"Call for a medical team at once!" Leatherhead ordered Mortu. "The Secrete should be on the way here. There's no telling how many internal injuries he has from proximity to that uncontrolled matter disintegration!"

Then he shoved his way to Donatello's side and began applying pressure to the most dangerous open wound that spilled blood like a waterfall.

"You can't die, Donnie!" Raph's own voice was low and choked with tears. "We just got you back!" He closed his hands on another gash in Don's leg that leaked alarmingly.

"I won't." Don looked around the circle once more. "I have...all of you to...protect me."

"You got it, bro." Mikey wiped at his beak. "We're here – so you gotta stay with us."

"I will. I promise."

It took but a few moments for the gentle hands to make it easier for Donatello to lie on the ground, to collect the mystical weapons that had been dropped in the turtles' haste to reach him. Byakko itself was unharmed; Zayton reverently lined it up with the others.

Leo turned, distracted for a moment by Kiryoku. When he looked back, he realized Don's eyes were on him.

"Don. Why'd...you do this? Why a sword like this?" It wasn't even among the first _hundred_ questions that mattered, but it was the only one he could voice against Don's dim eyes and roaring blood.

Donatello coughed. "Because...it was always yours. I...just had to find it."

"But what is it?"

"It's...it's the strongest thing I know."

"Magic?"

"Gravity. I survived the Architect...by remembering how much I wanted...to be back in my orbit around you...around all of you. I knew...something that got me this far would...be enough to finish the job...if it was in your hands, Leo."

Leo's throat closed with a lump of tears and he could only grip his brother's shoulder wordlessly.

But Don's eyes wandered up to Leatherhead and to Mortu on one side.

"Please don't...be offended. I don't mean…"

"We know, my brother," Leatherhead said gently. "We know."

"Your love for your original family does not lessen what we have attained," Mortu added. "You know that Utrom children have many parents. So too do you have many family."

Don managed a nod. "I missed them...but I missed you, too. Mortu, I…"

"Please, allow me," Leatherhead said, voice soothing. Don's face eased slightly as Leatherhead took up the explanation without ever releasing his hold on the blood that still tried to flow from Don's broken body. "Donatello had been in constant contact with us while we worked from within the ship's computers. Though we were not corporeal, we were able to communicate with him regularly while he was linked with the Architect and also when he worked alone from his room. He...spoke often of you, Mortu. As well as his brothers and Master Splinter, of course." Leatherhead gave them a nod.

Don twitched a hand and Mortu dropped lower to touch it with a foreleg. "I...I was glad you didn't have to go through it...like they did. But...it wasn't…"

"I understand," Mortu said. "I would have gone through anything to be with the rest of you, but I think I was more able to help you from here." He paused. Then, "But I will confess that I have not been whole since you were lost to us, Donatello. Zayton and Leatherhead are my brothers, they know this. But you...you made us a family. You pulled us together. You gave me something I never thought I would have for myself."

Don's mouth curved in a faint smile. "And you...gave me back...what I lost."

"And what you have again, my son," Splinter said, taking Don's other hand.

Don's eyes started to flutter shut.

"Where are the medics?" Zayton shouted in a shrill, near-panic.

"Hold on, Donnie!" Raph yelled at his brother. "Don't you stop fightin' now!"

"Donnie!" Mikey cried.

"Hold on, Donatello!" Mortu gripped Don's hand tightly.

"Stay with us, please!" Leo held onto Don's shoulder as though he would never let go.

Leatherhead roared as his own emotions broke loose. "Donatello!"

"My son!"

Donatello could not keep his eyes open any longer, even though he wanted to with all his heart. He wanted to tell them that he wasn't going to die here without a fight. That he couldn't leave them now that he finally had them all back at his side. That he was sorry and he loved them and he would always be with them even if he and his body couldn't agree on the terms.

But the words trickled away from him.

The last thing Donatello heard before he was swallowed by darkness was the Song of the Heart welcoming him home.

-==OOO==-

End of Act 7

-==OOO==-


End file.
